02/04/95
ASSEMBLY LANGUAGE/MACHINE LANGUAGE/CODING TUTORIAL -- Part ONE
BY SCATT
INDEX
-----
PREFIX
Part ONE : The Basics - An Introduction.
First Steps
Processors
Bits and Bytes!
Number Systems
A little on Computer MEMORY
ASCII
REGISTERS
Instruction Cycle
Machine Language
ASSEMBLERS
APPENDIX A: COMMODORE 64 MEMORY MAP ROM/RAM
APPENDIX B: Commodore 64 ROM Memory Map Routines
APPENDIX C: C64 KERNEL call addresses
APPENDIX D: OPCODES
APPENDIX E: C64 Kernal Jump Table
APPENDIX F: BASIC KEYWORDS
APPENDIX G: REU'S
APPENDIX H: ABOUT THE PROCESSOR CHIP
APPENDIX I: DIFFERENCES IN PROCESSORS
APPENDIX J: CHIP INFORMATION CHART
APPENDIX K: SPECIFICATIONS OF THE COMMODORE 64
BIBLIOGRAPHY
PREFIX
------
Hello Everyone..
This is my attempt to catalog everything I learn about Machine Language
(referred also as Machine Language and Coding) and put it into a simple
format for everyone who is interested in learning to try it out for
themselves. Every program that I have seen has been a bit too much for
me to comprehend, and too far advanced for me. So this is my attempt to
teach Assembly Language for the Commodore 64. Good luck, and if you want
to reach me for questions, please contact me at
ex240@cleveland.freenet.edu or as327@freenet.buffalo.edu
I AM NOT A PROGRAMMER! ALL I KNOW AS OF THIS VERY MOMENT
IS A SMALL AMOUNT OF BASIC, so please, Don't assume I know what I am
talking about. Let's just hope that the sources that I took all of this
data from were accurate. If you have something to dispute about this,
please e-mail me, and I will try to make updates. If you learn anything
new, that is not documented within the scope of this document, please,
write to me, and we'll see what we can find out TOGETHER!
Regards, SCATT
PS: If you see a number in parenthesis after a quote (i.e. "text"(4) ),
this means that the preceding text was taken from another source. Look
at the Bibliography in the end of this text file for the source.
--------------------------------------------------------
Part ONE : The Basics - An Introduction.
THE MAIN REASON for learning Assembly or ML is this: It is FASTER, and
SMALLER (memory-wise) then BASIC programs (which stands for Beginners
All-purpose Symbolic Instruction Code), and (ML Programs) give you an
insight to how the computer operates. And best of all, It brings us
CLOSER to the computer (which is every computer geek's goal!) haha..
"THE BEST WAY TO LEARN ANY PROGRAMMING LANGUAGE IS TO PROGRAM IN
THAT LANGUAGE."(7)
"BASIC might be compared to a reliable, comfortable car. It will take
you where you want to go. Machine language is like a sleek racing car -
you get there with lots of time to spare. When programming involves
large amounts of data, music, graphics, or games - speed can become the
single most important factor."(2)
"So, which language is best? (BASIC or ML) They are both best - but for
different purposes. Many programmers, after learning ML, find that they
continue to construct programs in BASIC, and then add ML modules where
speed is important. But perhaps the best reason of all for learning ML
is that it is fascinating and fun."(2) :)
OK let me tell you one other thing before we start. I assume (making an
ASS out of U and ME) that you understand how your computer basically
works. I am not going to attempt to "take a quick tour of the computers
internal parts," so please go get a book about this, ok? :)
There are definitions all over this thing (so TAKE NOTES!!) to explain
some of the terms but that's as far as I'm gonna go with it. An example
of what you should already know is like what exactly memory is! What is
memory? It is actually little switches and each one can have two states:
on or off! Did you know that? IF NOT, then this is not for you! Well,
not yet that is! Do you know what I/O, ROM, RAM, etc is? IF NOT, again,
this is not for you YET! You need to start out elsewhere! I don't mean
to be rude, but we all have our starting points! OK? Now SMILE! And do
what must be done in order to get up to this point. Machine Language
programming is not something to rush into...
There are A LOT of books around this wide planet, so whether you get your
information from comp.cbm or a library, or whatever, ask people! Visit
your library! GO! GO NOW! Don't wait another minute or else it's gonna
be too late!!!!!!!!! :)
First Steps
-----------
I would recommend that you either get a Commodore 64 (If you don't
already have one) or a good emulator program. One emulator I recommend
is C64S. Ask around, especially on IRC #c-64. They should all know
where to get it.
Once you have your C64 or emulator, I recommend you get an Assembler.
Again, ask around. You will have one in no time.
One other thing: "Many of the first home computerists in the 1970's
learned ML before they learned BASIC. This is because an average version
of the BASIC language used in microcomputers takes up around 12,000 bytes
of memory, and early personal computers (KIM, AIM, etc.) were severely
restricted by containing only a small amount of available memory. These
early machines were unable to offer BASIC, so everyone programmed in
ML."(2) So hey! ML is not more difficult to understand than BASIC. (But
sometimes more of a challenge to debug) But it's not too far beyond
BASIC. So DIG IN ALREADY!
Processors
----------
Another thing: I'm not sure which processor is in the different versions
of the C=64. I have seen 6502, and 6510. When I figure it out, I will
update this again! As of this point, I am not sure that all of the
commands in this book will work on the C=64. We will learn together
though, won't we!
Well, I found some more info on the CPU. "The heart of your machine
(C=64) is the 40-pin chip just to the left of the RF modulator can. (He
is talking about the old-style case) This is the 6510A microprocessor."(4)
He also states that "This 40-pin custom chip operates like a 6502 MPU
(also known as CPU) except the 6510 has a built-in 6-bit peripheral I/O
port that controls memory management and cassette I/O."
Bits and Bytes!
--------------
"It's interesting that the word "bit" is frequently explained as a
shortening of the phrase BInary digiT. In fact, the word bit goes back
several centuries. There was a coin which was soft enough to be cut
with a knife into eight pieces. Hence, pieces of eight. A single piece
of this coin was called a bit and, as with computer memories, it meant
that you couldn't slice it any further. We still use the word bit today
as in the phrase "two bits" meaning 25 cents."(2)
A byte is 8 bits of data that may be loaded together into a register. A
register holds 1 byte. The 6502 can only affect 1 byte in one
operation. Because the 6502 can perform hundreds of thousands of
operations a second, it can affect 100's of 1000's of bytes per second.
In fact, "the Commodore 64 can handle about 500,000 of these steps each
second." This is from the C-64 Troubleshooting & Repair Guide by Robert
C. Brenner.
Number Systems
----------------------
DECimal Numbers: We all know what these are, like 0,1,2,3 etc. These
are base 10 numbers. ML can be accomplished in Decimal, but very rarely
seen.
*BINary Numbers: Binary numbers are base 2 numbers. All we have to
remember in Binary numbers is 0's and 1's. It's supposedly how the
computer "thinks". What I take this as is that it's the way the
processor sends and receives data internally (through it's 8-bit
channel.) with 1's (or positive voltage) and 0's or a lack of voltage.
All digits and numbers are converted to BIN. The easiest way to convert
DECimal numbers to Binary is this:
Place 0 0 0 0 Here we have 1's place, 2's place,
Holder-> 8 4 2 1 4's place and 8's place and so on..
-------
Bin Num-> 0 0 0 0 Here's the binary number..
So, if we have a binary number of let's say, 0101, then we just add up
the place's numbers and see what decimal number we get.. So we have a 1
in the 4's place, so that's decimal #4. We have no 8's or 2's and we
have 1 in the 1's place. So if we add the 4 to the 1, we get a decimal
of 5. So, if we had let's say a decimal number of like 12, we would
know that there is at least one 8, and a 4, and we come up with
1100(bin)=12(dec)! Try some on your own and get familiar converting
these back and fourth.....
BINARY DECIMAL BINARY DECIMAL
------ ------- ------ -------
0000 0 0110 6
0001 1 0111 7
0010 2 1000 8
0011 3 1001 9
0100 4 1010 10
0101 5 1011 11
The Bit significance and the byte..
Bit Number: b7 b6 b5 b4 b3 b2 b1 b0
Bit Significance: 128 64 32 16 8 4 2 1
Binary Number: 0 0 0 0 0 0 0 0
This would be an 8-BIT Binary number. Often written as 0000 0000.
Understood? Kool. So the Decimal number "25" would convert to what? Yup,
you got it, 0001 1001 !!!
The rightmost Bit=Bit 0 (Tells us whether we have a 1 in our byte) The
next to the left (Bit 1) tells us whether we have a two, etc..
And we go ON!
*HEX Numbers: Hexadecimal Numbers are Base 16. "HEX" for 6, and DECI for
10, so when you add them, 6+10=16!!! :) Kool. That is, multiples of 16.
0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f. When we program (or the new word seems
to be "code" or shall I say the "in" word haha..) So when we CoDe, we use
a "$" to represent HEX numbers. Remember this. Put it into your ROM and
KEEP IT THERE! It is important!
"See how hex $10 (see the dollar-sign?) looks like binary? If you split
a hex number into two parts, 1 and 0, and the binary (it's an eight-bit
group, a byte) into two parts, 0001 and 0000 - you can see the
relationship."(2)
Remember when I did this: 0000 0000? Well, some people consider one of
those sets of 4 bits to be a "nybble". To represent a byte (8-bits) in
HEX notation, divide the 8-bit byte into two 4-bit units (yup, that's a
nybble). Each of the 4-bit units (or nybbles) has a value of from 0 to
15 (decimal) which we express with a single hexadecimal digit! So you
can use just ONE hexadecimal digit to represent 1 nybble (4-bits)! Isn't
that kool! Now you remembered that the "$" represents the HEX notation,
right? Well, check out this chart:
HEX DECIMAL
--- ----
$0 = 0
$01 = 1
$02 = 2
$03 = 3
$04 = 4
$05 = 5
$06 = 6
$07 = 7
$08 = 8 (gee this gets boring..)
$09 = 9
$0A = 10 (what's this? WO! an "A"!!!)
$0B = 11
$0C = 12
$0D = 13
$0E = 14
$0F = 15
$10 = 16
$11 = 17
$12 = 18
$13 = 19
etc
etc
So there we have it..
Here's another way to put it:
" DECIMAL 0 1 2 3 4 5 6 7 8 9 then you start over with 10
HEX 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F then you
start over with 10"(2)
Let me go and see if I can find some text on how to mathematically
convert decimal to hex.. I'll be right back..
Well, I didn't find what I was looking for, but I found this little charm..
"Microsoft Hex-Decimal Converter"(2)
1 HE$="0123456789ABCDEF"
2 ?"{CLEAR}{03 DOWN}PLEASE CHOOSE:
4 ?"{03 DOWN}{03 RIGHT}1-INPUT HEX & GET DECIMAL BACK.
5 REM NEW LINE HERE
6 ?"{02 DOWN}{03 RIGHT}2-INPUT DECIMAL TO GET HEX BACK.
7 GET K:IF K=0 THEN GOTO 7
9 ?"{CLEAR}":ON K GOTO 200,400
100 H$="":FOR M=3 TO 0 STEP -1:N%=DE/(16^M):
DE=DE-N%*16^M:H$=H$+MID$(HE$,N%+1,1):NEXT
101 RETURN
102 D=0:Q=3:FOR M=1 TO 4:FOR W=0 TO 15:
IF MID$(H$,M,1)=MID$(HE$,W+1,1) THEN GOTO 104
103 NEXT W
104 D1=W*(16^(Q)):D=D+D1:Q=Q-1:NEXT M
105 DE=INT(D):RETURN
200 INPUT"{02 DOWN}HEX";H$:GOSUB 102:
PRINT SPC(11)"{UP}= {REV}"DE"{LEFT} "
210 GOTO 200
400 INPUT"{02 DOWN}DECIMAL";DE:GOSUB 100:
PRINT SPC(14)"{UP}= {REV} "H$" "
410 GOTO 400
Something useful: "To figure out a HEX number, multiply the second column
by 16 and add the other number to it. So, $1A would be one times 16 plus
10 (Recall that A stands for ten)."(2)
Well, since I sent in my $$ to register "The PC Assembler Tutor" and never got
anything back from the guy, I will ASSUME (ASS-U-ME) that Mr. Nelson
won't mind me reproducing this next goody without his consent. (Although
I did mention his name to keep him happy! :)
HEX CONVERT BINARY
--- ------- -------
"3 -> 2 + 1 -> 0011
9 -> 8 + 1 -> 1001
F = 15 -> 8+4+2+1 -> 1111
All computers operate on binary data, so why do we use hex
numbers? Take a test. Copy these two binary numbers:
1011 1000 0110 1010 1001 0101 0111 1010
0111 1100 0100 1100 0101 0110 1111 0011
Now copy these two hex numbers:
B86A957A
7C4C56F3
As you can see, you recognize hex numbers faster and you make
fewer mistakes in transcription with hex numbers.
ADDITION AND SUBTRACTION
The rules for binary addition are easy:
0 + 0 = 0
0 + 1 = 1
1 + 0 = 1
1 + 1 = 0 (carry 1 to the next digit left)
similarly for binary subtraction:
0 - 0 = 0
0 - 1 = 1 (borrow 1 from the next digit left)
1 - 0 = 1
1 - 1 = 0" (8)
OK.. I hope that clears some stuff up.. Well, for now, I can't find much
on converting Decimal numbers to Hex, so as the book states "Even the
sketchiest understanding of hexadecimal math, however, should be
sufficient for you to follow and use (assembly)"(1)
and...
"You need not memorize (HEX NUMBERS) beyond learning to count from 1 to
16 - learning the symbols. Be able to count from 00 up to 0F. (By
convention, even the smallest hex number is listed as two digits as in 03
or 0B."(2)
So, what I would recommend you do (and what I will be doing before not
too long) is copying a DEC to HEX table from somewhere (or just make your
own) and tape it in front of you, avoiding the monitor you are using for
a billboard, and you will then know how to convert DEC to HEX or visa
versa.
As I've heard somewhere before, and also very useful, "Most ML programming
involves working with hex numbers only between 0 and 255. This is
because a single byte (8-bits) can hold no number larger than 255.
Manipulating numbers larger than 255 is no real importance in ML
programming until you are ready to work with more advanced ML programs.
For example, all 6502 ML instructions are coded into one byte, all the
"flags" are held in one byte, and many "addressing modes" use one byte to
hold their argument."(2)
A little on Computer MEMORY
---------------------------
I'm sorry to use so many quotes, but everything I've found seems so
useful, and I am learning so much from all of this info, I just can't
stop! And all the typing is very good for my fingers..
"THE CITY OF BYTES
Imagine a city with a single long row of houses. It's night. Each house
has a peculiar Christmas display: on the roof is a line of eight lights.
The houses represent bytes; each light is a single bit. If we fly over
the city of bytes, at first we see only darkness. Each byte contains
nothing (zero), so all eight of its bulbs are off. (On the horizon we can
see a glow, however, because the computer has memory up there, called ROM
memory, which is very active and contains built-in programs.) But we are
down in RAM, our free user-memory, and there are no programs now in RAM,
so every house is dark. Let's observe what happens to an individual byte
when different numbers are stored there; we can randomly choose byte
1504. We hover over that house to see what information is "contained" in
the light display.
____.____.____.____.____.____.____.____.____("."=off, "o"=on)
Like all the rest, this byte is dark. Each bulb is off. Observing this,
we know that the byte here is "holding" or representing a zero. If
someone at the computer types in POKE 1504,1 - suddenly the rightmost
light bulb goes on and the byte holds a one instead of a zero:
____.____.____.____.____.____.____.____o____
This rightmost bulb is in the 1's column (just as it would be in our
usual way of counting by ten's, our familiar decimal system). But the
next bulb is in a 2's column, so POKE 1504,2 would be:
____.____.____.____.____.____.____o____.____
And three would be one and two:
____.____.____.____.____.____.____o____o____
In this way - by checking which bits are turned on and then adding them
together - the computer can look at a byte and know what number is
there. Each light bulb, each BIT, is in its own special position in the
row of eight and has a value twice the value of the one just before it:
____o____o____o____o____o____o____o____o____ = 255!
128's 64's 32's 16's 8's 4's 2's 1's
65535 is an interesting number because it represents the limit of our
computer's memories. In special cases, with additional hardware, memory
can be expanded beyond this. But this is the normal upper limit because
the 6502 chip is designed to be able to address (put bytes in or take
them out of memory cells) up to $FFFF."(2)
ASCII
-------
"Instead of a number from 0 to 255, an 8-bit byte can be used to
represent an upper or lower case letter of the alphabet, a punctuation
mark, or a printer-control character such as a carriage return."(1)
ASCII-American Standard Code for Information Interchange. You've heard it
a million times, and will hear it a million more. It is the "closest
thing the industry has to a standard set of character codes."(1) So,
"Whether a given byte is interpreted as a number, an ASCII character, or
something else depends entirely on the program using that byte."(1)
REGISTERS
---------------
A register is a special area in memory for storing the data upon which
the program is operating.
Three Registers in the 6502 Processor:
A- Accumulator - Can add or subtract any number up to 255
X, and Y - These can either be used to add one or subtract
one digit.
" The "A" register is often called the accumulator which indicates its
function: all math and logical manipulations are done to the "A" register (from
here on out it will be referred to as .A).
There are two other registers inside the 6502 processor, specifically .X and
.Y. These registers help act as counters and indexes into memory (sort of like
mem[x] in pascal but not quite...)."(7)
The 6502 can set one register equal to any other register.
Instruction Cycle
---------------------
*The 6502 only knows 151 instructions called opcodes. (I'm not sure if
this has changed in the C=64, but I will find out. and update this) Each
opcode is 1-byte (8-bits) long. Opcodes tell the processor what to do.
The processor gets the first opcode, preforms the specified operation,
gets the next opcode, preforms the operation, etc.
So where does the processor get the list of opcodes? You got it, from the
program. The 6502 has a PC (Program Counter) that tells it where to get
the next opcode from in memory. The PC stores the address of some
location in memory. When the processor starts it's instruction cycle, it
looks at the PC, gets the memory location for the first op- code, goes
there, and preforms the operation specified by that opcode. When it's
done with the first one, it MAKES the PC point to the next opcode. So
the processor uses the PC as sort of a MAP. Then, it again looks at the
PC and gets the memory location back and goes there and starts over again.
Here's a cool flowchart:
[---------------------------]
[ Fetch opcode pointed to ]
[ by the PC (Program ]<-----\
[ counter. ] |
[---------------------------] |
| |
\|/ |
[---------------------------] |
[ Perform operation ] |
[ specified by opcode ] |
[---------------------------] |
| |
\|/ |
[---------------------------] |
[ Make PC (Program Counter)] |
[ point to next opcode in ] |
[ memory ] |
[---------------------------] |
| |
|____________________|
Cool, eh?
This is the 6502 Instruction Cycle.
MACHINE LANGUAGE
----------------------
Machine Language program is nothing more then a series of ML instructions
stored in memory. Each ML instruction is stored in memory as a 1-byte
(8-bit) long opcode which may be followed by 1 or 2 bytes of operand. ML
is usually in hexadecimal format. So, here is a short ML program: A9 05
20 02 04 A2 F5 60 Yup. Just a bunch of numbers! cool.
ASSEMBLERS
------------
"To make it easier to write programs in machine language (called "ML"
from here on), most programmers use a special program called an
assembler. This is where the term "assembly language" comes from. ML
and assembly language programs are both essentially the same thing.
Using an assembler to create ML programs is far easier than being forced
to look up and then POKE each byte into RAM memory. That's the way it
used to be done, when there was too little memory in computers to hold
languages (like BASIC or Assemblers) at the same time as programs created
by those languages. That old style hand-programming was very
laborious."(2)
"Program (which) takes source code in basic form or from a file and
writes to memory or a file the resulting executable. Allows higher
flexibility than a monitor (see below) due to use of labels etc and not
having to keep track of each address within the program.
Monitor - A program, resident in memory, invoked by a SYS call from basic
or by hitting the restore key that will let you disassemble, assemble and
examine areas of memory and execute programs directly from the monitor.
Useful for debugging programs and for writing short programs."(7)
One monitor that I've seen is the MLX monitor.
Object Code: is a series of 6502 machine language instructions to be
stored in memory and executed.
Source Code: An assembly language source program consists of one or more
lines of assembly language source code. These consist of 4 fields:
LABEL ---- MNEMONIC ---- OPERAND ---- COMMENT
Label is a name given to the instruction. Similar to BASIC line numbers.
Mnemonic is a cool word! It is the 3-letter name that suggests a
function of a given ML instruction. (Easy! -- like LDA, LDX, or LDY...
we'll get into these later.)
Operand would be the action of the Mnemonic. It's like this:
LDA $0300 <---operand... in this case we're loading
the accumulator with $0300..
LABEL- This is an optional field. This is where you put your comments.
You separate the Label from the rest of the instruction with a ";"
(semicolon).. This makes the source code more understandable.
Here's another cool flowchart:
Source of input--> PROGRAMMER
|
\|/
What he/she inputs--> SOURCE CODE
|
\|/
Program that converts ---> ASSEMBLER
Source code to ML |
/ \
/ \
/ \
/ \
Output: Assembler Object
listing code
| |
Intended for the: Programmer Processor
OK! Now if any of this is a bit confusing, look it over, and get used to
it! You will be responsible for having this stuff in the back of your
head at ALL TIMES!!! Good luck.. Next up is some Mnemonics!
See you all then!
APPENDIX A
----------
COMMODORE 64 MEMORY MAP ROM/RAM
; Data types in headers (for reassembler):
;
; DATA Misc data
; TEXT String terminated with 00
; WORD Vectors in LO/HI byte pairs
; CHIP I/O Area
; EMPTY ROM containing FF's or AA's
;
HEX DECIMAL BITS DESCRIPTION
0000 0 7-0 MOS 6510 Data Direction
Register (xx101111)
Bit= 1: Output, Bit=0:
Input, x=Don't Care
0001 1 MOS 6510 Micro-Processor
On-Chip I/O Port
0 /LORAM Signal (0=Switch BASIC ROM Out)
1 /HIRAM Signal (0=Switch Kernal ROM Out)
2 /CHAREN Signal (O=Swith Char. ROM In)
3 Cassette Data Output Line
4 Cassette Switch Sense: 1 = Switch Closed
5 Cassette Motor Control
O = ON, 1 = OFF
6-7 Undefined
D6510 0000 0 6510 On-chip Data Direction Register.
R6510 0001 1 6510 On-chip 8-bit Input/Output Register.
TEMP 0002 2 Unused. Free for user programs.
ADRAY1 0003-0004 3 Jump Vector: Convert FAC to Integer in (A/Y)
($B1AA).
ADRAY2 0005-0006 5 Jump Vector: Convert Integer in (A/Y) to
Floating point in (FAC); ($B391).
CHARAC 0007 7 Search Character/Temporary Integer during INT.
ENDCHR 0008 8 Flag: Scan for Quote at end of String.
INTEGR 0007-0008 7 Temporary Integer during OR/AND.
TRMPOS 0009 9 Screen Column for last TAB.
VERCK 000A 10 Flag: 0 = Load, 1 = Verify.
COUNT 000B 11 Input Buffer Pointer/Number of Subscripts.
DIMFLG 000C 12 Flag: Default Array dimension.
VALTYP 000D 13 Data type Flag: $00 = Numeric, $FF = String.
INTFLG 000E 14 Data type Flag: $00 = Floating point, $80 =
Integer.
GARBFL 000F 15 Flag: DATA scan/List Quote/Garbage collection.
SUBFLG 0010 16 Flag: Subscript reference/User Function call.
INPFLG 0011 17 Input Flag: $00 = INPUT, $40 = GET, $98 =
READ.
TANSGN 0012 18 Flag: TAN sign/Comparative result.
CHANNL 0013 19 File number of current Input Device.
LINNUM 0014-0015 20 Temporary: Integer value.
TEMPPT 0016 22 Pointer: Temporary String Stack.
LASTPT 0017-0018 23 Last temporary String Address.
TEMPST 0019-0021 25 Stack for temporary Strings.
INDEX 0022-0025 34 Utility Pointer Area.
INDEX1 0022-0023 34 First Utility Pointer.
INDEX2 0024-0025 36 Secong Utility Pointer.
RESHO 0026-002A 38 Floating point product of Multiply and
Divide.
TXTTAB 002B-002C 43 Pointer: Start of BASIC Text Area ($0801).
VARTAB 002D-002E 45 Pointer: Start of BASIC Variables.
ARYTAB 002F-0030 47 Pointer: Start of BASIC Arrays.
STREND 0031-0032 49 Pointer: End of BASIC Arrays + 1.
FRETOP 0033-0034 51 Pointer: Bottom of String space.
FRESPC 0035-0036 53 Utility String Pointer.
MEMSIZ 0037-0038 55 Pointer: Highest Address available to BASIC
($A000).
CURLIN 0039-003A 57 Current BASIC Line number.
OLDLIN 003B-003C 59 Previous BASIC Line number.
OLDTXT 003D-003E 61 Pointer: BASIC Statement for CONT.
DATLIN 003F-0040 63 Current DATA Line number.
DATPTR 0041-0042 65 Pointer: Used by READ - current DATA Item
Address.
INPPTR 0043-0044 67 Pointer: Temporary storage of Pointer during
INPUT Routine.
VARNAM 0045-0046 69 Name of Variable being sought in Variable
Table.
VARPNT 0047-0048 71 Pointer: to value of (VARNAM) if Integer, to
descriptor if String.
FORPNT 0049-004A 73 Pointer: Index Variable for FOR/NEXT loop.
VARTXT 004B-004C 75 Temporary storage for TXTPTR during READ,
INPUT and GET.
OPMASK 004D 77 Mask used during FRMEVL.
TEMPF3 004E-0052 78 Temporary storage for FLPT value.
FOUR6 0053 83 Length of String Variable during Garbege
collection.
JMPER 0054-0056 84 Jump Vector used in Function Evaluation -
JMP followed by Address ($4C,$LB,$MB).
TEMPF1 0057-005B 87 Temporary storage for FLPT value.
TEMPF2 005C-0060 92 Temporary storage for FLPT value.
FAC 0061-0066 97 Main Floating point Accumulator.
FACEXP 0061 97 FAC Exponent.
FACHO 0062-0065 98 FAC Mantissa.
FACSGN 0066 102 FAC Sign.
SGNFLG 0067 103 Pointer: Series Evaluation Constant.
BITS 0068 104 Bit Overflow Area during normalisation
Routine.
AFAC 0069-006E 105 Auxiliary Floating point Accumulator.
ARGEXP 0069 105 AFAC Exponent.
ARGHO 006A-006D 106 AFAC Mantissa.
ARGSGN 006E 110 AFAC Sign.
ARISGN 006F 111 Sign of result of Arithmetic Evaluation.
FACOV 0070 112 FAC low-order rounding.
FBUFPT 0071-0072 113 Pointer: Used during CRUNCH/ASCII conversion.
CHRGET 0073-008A 115 Subroutine: Get next Byte of BASIC Text.
,0073 INC $7A ,0082 BEQ $0073
,0075 BNE $0079 ,0084 SEC
,0077 INC $7B ,0085 SBC #$30
! ,0079 LDA $0801 ,0087 SEC
,007C CMP #$3A ,0088 SBC #$D0
,007E BCS $008A ,008A RTS
,0080 CMP #$20
CHRGOT 0079 121 Entry to Get same Byte again.
TXTPTR 007A-007B 122 Pointer: Current Byte of BASIC Text.
RNDX 008B-008F 139 Floating RND Function Seed Value.
STATUS 0090 144 Kernal I/O Status Word ST.
STKEY 0091 145 Flag: $7F = STOP key.
SVXT 0092 146 Timing Constant for Tape.
VERCKK 0093 147 Flag: 0 = Load, 1 = Verify.
C3PO 0094 148 Flag: Serial Bus - Output Character buffered.
BSOUR 0095 149 Buffered Character for Serial Bus.
SYNO 0096 150 Cassette Sync. number.
TEMPX 0097 151 Temporary storage of X Register during CHRIN.
TEMPY 0097 151 Temporary storage of Y Register during RS232
fetch.
LDTND 0098 152 Number of Open Files/Index to File Table.
DFLTN 0099 153 Default Input Device (0).
DFLTO 009A 154 Default Output Device (3).
PRTY 009B 155 Parity of Byte Output to Tape.
DPSW 009C 156 Flag: Byte received from Tape.
MSGFLG 009D 157 Flag: $00 = Program mode: Suppress Error
Messages, $40 = Kernal Error Messages only,
$80 = Direct mode: Full Error Messages.
FNMIDX 009E 158 Index to Cassette File name/Header ID for
Tape write.
PTR1 009E 158 Tape Error log pass 1.
PTR2 009F 159 Tape Error log pass 2.
TIME 00A0-00A2 160 Real-time jiffy Clock (Updated by IRQ
Interrupt approx. every 1/60 of Second);
Update Routine: UDTIMK ($F69B).
TSFCNT 00A3 163 Bit Counter Tape Read or Write/Serial Bus
EOI (End Of Input) Flag.
TBTCNT 00A4 164 Pulse Counter Tape Read or Write/Serial Bus
shift Counter.
CNTDN 00A5 165 Tape Synchronising count down.
BUFPNT 00A6 166 Pointer: Tape I/O buffer.
INBIT 00A7 167 RS232 temporary for received Bit/Tape
temporary.
BITC1 00A8 168 RS232 Input Bit count/Tape temporary.
RINONE 00A9 169 RS232 Flag: Start Bit check/Tape temporary.
RIDATA 00AA 170 RS232 Input Byte Buffer/Tape temporary.
RIPRTY 00AB 171 RS232 Input parity/Tape temporary.
SAL 00AC-00AD 172 Pointer: Tape Buffer/Screen scrolling.
EAL 00AE-00AF 174 Tape End Address/End of Program.
CMPO 00B0-00B1 176 Tape timing Constants.
TAPE1 00B2-00B3 178 Pointer: Start Address of Tape Buffer ($033C).
BITTS 00B4 180 RS232 Write bit count/Tape Read timing Flag.
NXTBIT 00B5 181 RS232 Next Bit to send/Tape Read - End of
Tape.
RODATA 00B6 182 RS232 Output Byte Buffer/Tape Read Error Flag.
FNLEN 00B7 183 Number of Characters in Filename.
LA 00B8 184 Current File - Logical File number.
SA 00B9 185 Current File - Secondary Address.
FA 00BA 186 Current File - First Address (Device number).
OPEN LA,FA,SA; OPEN 1,8,15,"I0":CLOSE 1
FNADR 00BB-00BC 187 Pointer: Current File name Address.
ROPRTY 00BD 189 RS232 Output Parity/Tape Byte to be Input or
Output.
FSBLK 00BE 190 Tape Input/Output Block count.
MYCH 00BF 191 Serial Word Buffer.
CAS1 00C0 192 Tape Motor Switch.
STAL 00C1-00C2 193 Start Address for LOAD and Cassette Write.
MEMUSS 00C3-00C4 195 Pointer: Type 3 Tape LOAD and general use.
LSTX 00C5 197 Matrix value of last Key pressed; No Key = $40.
NDX 00C6 198 Number of Characters in Keyboard Buffer
queue.
RVS 00C7 199 Flag: Reverse On/Off; On = $01, Off = $00.
INDX 00C8 200 Pointer: End of Line for Input (Used to
suppress trailing spaces).
LXSP 00C9-00CA 201 Cursor X/Y (Line/Column) position at start of
Input.
SFDX 00CB 203 Flag: Print shifted Characters.
BLNSW 00CC 204 Flag: Cursor blink; $00 = Enabled, $01 =
Disabled.
BLNCT 00CD 205 Timer: Count down for Cursor blink toggle.
GDBLN 00CE 206 Character under Cursor while Cursor Inverted.
BLNON 00CF 207 Flag: Cursor Status; $00 = Off, $01 = On.
CRSW 00D0 208 Flag: Input from Screen = $03, or Keyboard =
$00.
PNT 00D1-00D2 209 Pointer: Current Screen Line Address.
PNTR 00D3 211 Cursor Column on current Line, including
Wrap-round Line, if any.
QTSW 00D4 212 Flag: Editor in Quote Mode; $00 = Not.
LNMX 00D5 213 Current logical Line length: 39 or 79.
TBLX 00D6 214 Current Screen Line number of Cursor.
SCHAR 00D7 215 Screen value of current Input Character/Last
Character Output.
INSRT 00D8 216 Count of number of inserts outstanding.
LDTB1 00D9-00F2 217 Screen Line link Table/Editor temporaries.
High Byte of Line Screen Memory Location.
USER 00F3-00F4 243 Pointer: Current Colour RAM Location.
KEYTAB 00F5-00F6 245 Vector: Current Keyboard decoding Table.
($EB81)
RIBUF 00F7-00F8 247 RS232 Input Buffer Pointer.
ROBUF 00F9-00FA 249 RS232 Output Buffer Pointer.
FREKZP 00FB-00FE 251 Free Zero Page space for User Programs.
BASZPT 00FF 255 BASIC temporary Data Area.
ASCWRK 00FF-010A 255 Assembly Area for Floating point to ASCII
conversion.
BAD 0100-013E 256 Tape Input Error log.
STACK 0100-01FF 256 6510 Hardware Stack Area.
BSTACK 013F-01FF 319 BASIC Stack Area.
BUF 0200-0258 512 BASIC Input Buffer (Input Line from Screen).
LAT 0259-0262 601 Kernal Table: Active logical File numbers.
FAT 0263-026C 611 Kernal Table: Active File First Addresses
(Device numbers).
SAT 026D-0276 621 Kernal Table: Active File Secondary
Addresses.
KEYD 0277-0280 631 Keyboard Buffer Queue (FIFO).
MEMSTR 0281-0282 641 Pointer: Bottom of Memory for Operating
System ($0800).
MEMSIZ 0283-0284 643 Pointer: Top of Memory for Operating
System ($A000).
TIMOUT 0285 645 Serial IEEE Bus timeout defeat Flag.
COLOR 0286 646 Current Character Colour code.
GDCOL 0287 647 Background Colour under Cursor.
HIBASE 0288 648 High Byte of Screen Memory Address ($04).
XMAX 0289 649 Maximum number of Bytes in Keyboard
Buffer ($0A).
RPTFLG 028A 650 Flag: Repeat keys; $00 = Cursors, INST/DEL &
Space repeat, $40 no Keys repeat, $80 all
Keys repeat ($00).
KOUNT 028B 651 Repeat Key: Speed Counter ($04).
DELAY 028C 652 Repeat Key: First repeat delay Counter ($10).
SHFLAG 028D 653 Flag: Shift Keys: Bit 1 = Shift, Bit 2 = CBM,
Bit 3 = CTRL; ($00 = None, $01 = Shift, etc.).
LSTSHF 028E 654 Last Shift Key used for debouncing.
KEYLOG 028F-0290 655 Vector: Routine to determine Keyboard table
to use based on Shift Key Pattern ($EB48).
MODE 0291 657 Flag: Upper/Lower Case change: $00 = Disabled,
$80 = Enabled ($00).
AUTODN 0292 658 Flag: Auto scroll down: $00 = Disabled ($00).
M51CTR 0293 659 RS232 Pseudo 6551 control Register Image.
M51CDR 0294 660 RS232 Pseudo 6551 command Register Image.
M51AJB 0295-0296 661 RS232 Non-standard Bits/Second.
RSSTAT 0297 663 RS232 Pseudo 6551 Status Register Image.
BITNUM 0298 664 RS232 Number of Bits left to send.
BAUDOF 0299-029A 665 RS232 Baud Rate; Full Bit time microseconds.
RIDBE 029B 667 RS232 Index to End of Input Buffer.
RIDBS 029C 668 RS232 Pointer: High Byte of Address of Input
Buffer.
RODBS 029D 669 RS232 Pointer: High Byte of Address of Output
Buffer.
RODBE 029E 670 RS232 Index to End of Output Buffer.
IRQTMP 029F-02A0 671 Temporary store for IRQ Vector during Tape
operations.
ENABL 02A1 673 RS232 Enables.
TODSNS 02A2 674 TOD sense during Tape I/O.
TRDTMP 02A3 675 Temporary storage during Tape READ.
TD1IRQ 02A4 676 Temporary D1IRQ Indicator during Tape READ.
TLNIDX 02A5 677 Temporary for Line Index.
TVSFLG 02A6 678 Flag: TV Standard: $00 = NTSC, $01 = PAL.
TEMP 02A7-02FF 679 Unused.
SPR11 02C0-02FE 704 Sprite #11 Data Area.
(SCREEN + $03F8 + SPR number)
POKE 1024+1016+0,11 to use Sprite#0 DATA
from ($02C0-$02FE).
IERROR 0300-0301 768 Vector: Indirect entry to BASIC Error
Message, (X) points to Message ($E38B).
IMAIN 0302-0303 770 Vector: Indirect entry to BASIC Input Line
and Decode ($A483).
ICRNCH 0304-0305 772 Vector: Indirect entry to BASIC Tokenise
Routine ($A57C).
IQPLOP 0306-0307 774 Vector: Indirect entry to BASIC LIST
Routine ($A71A).
IGONE 0308-0309 776 Vector: Indirect entry to BASIC Character
dispatch Routine ($A7E4).
IEVAL 030A-030B 778 Vector: Indirect entry to BASIC Token
evaluation ($AE86).
SAREG 030C 780 Storage for 6510 Accumulator during SYS.
SXREG 030D 781 Storage for 6510 X-Register during SYS.
SYREG 030E 782 Storage for 6510 Y-Register during SYS.
SPREG 030F 783 Storage for 6510 Status Register during SYS.
USRPOK 0310 784 USR Function JMP Instruction ($4C).
USRADD 0311-0312 785 USR Address ($LB,$MB).
TEMP 0313 787 Unused.
CINV 0314-0315 788 Vector: Hardware IRQ Interrupt Address ($EA31).
CNBINV 0316-0317 790 Vector: BRK Instruction Interrupt Address
($FE66).
NMINV 0318-0319 792 Vector: Hardware NMI Interrupt Address ($FE47).
IOPEN 031A-031B 794 Vector: Indirect entry to Kernal OPEN
Routine ($F34A).
ICLOSE 031C-031D 796 Vector: Indirect entry to Kernal CLOSE
Routine ($F291).
ICHKIN 031E-031F 798 Vector: Indirect entry to Kernal CHKIN
Routine ($F20E).
ICKOUT 0320-0321 800 Vector: Indirect entry to Kernal CHKOUT
Routine ($F250).
ICLRCH 0322-0323 802 Vector: Indirect entry to Kernal CLRCHN
Routine ($F333).
IBASIN 0324-0325 804 Vector: Indirect entry to Kernal CHRIN
Routine ($F157).
IBSOUT 0326-0327 806 Vector: Indirect entry to Kernal CHROUT
Routine ($F1CA).
ISTOP 0328-0329 808 Vector: Indirect entry to Kernal STOP
Routine ($F6ED).
IGETIN 032A-032B 810 Vector: Indirect entry to Kernal GETIN
Routine ($F13E).
ICLALL 032C-032D 812 Vector: Indirect entry to Kernal CLALL
Routine ($F32F).
USRCMD 032E-032F 814 User Defined Vector ($FE66).
ILOAD 0330-0331 816 Vector: Indirect entry to Kernal LOAD
Routine ($F4A5).
ISAVE 0332-0333 818 Vector: Indirect entry to Kernal SAVE
Routine ($F5ED).
TEMP 0334-033B 820 Unused.
TBUFFR 033C-03FB 828 Tape I/O Buffer.
SPR13 0340-037E 832 Sprite #13.
SPR14 0380-03BE 896 Sprite #14.
SPR15 03C0-03FE 960 Sprite #15.
TEMP 03FC-03FF 1020 Unused.
VICSCN 0400-07E7 1024 Default Screen Video Matrix.
TEMP 07E8-07F7 2024 Unused.
SPNTRS 07F8-07FF 2040 Default Sprite Data Pointers.
0800-9FFF 2048 Normal BASIC Program space.
8000-9FFF 32768 Optional Cartridge ROM space.
A000-BFFF 40960 BASIC ROM (Part) or 8 KB RAM.
a000 40960 - Restart Vectors WORD
a00c 40972 stmdsp BASIC Command Vectors WORD
a052 41042 fundsp BASIC Function Vectors WORD
a080 41088 optab BASIC Operator Vectors WORD
a09e 41118 reslst BASIC Command Keyword Table DATA
a129 41257 msclst BASIC Misc. Keyword Table DATA
a140 41280 oplist BASIC Operator Keyword Table DATA
a14d 41293 funlst BASIC Function Keyword Table DATA
a19e 41374 errtab Error Message Table DATA
a328 41768 errptr Error Message Pointers WORD
a364 41828 okk Misc. Messages TEXT
a38a 41866 fndfor Find FOR/GOSUB Entry on Stack
a3b8 41912 bltu Open Space in Memory
a3fb 41979 getstk Check Stack Depth
a408 41992 reason Check Memory Overlap
a435 42037 omerr Output ?OUT OF MEMORY Error
a437 42039 error Error Routine
a469 42089 errfin Break Entry
a474 42100 ready Restart BASIC
a480 42112 main Input & Identify BASIC Line
a49c 42140 main1 Get Line Number & Tokenise Text
a4a2 42146 inslin Insert BASIC Text
a533 42291 linkprg Rechain Lines
a560 42336 inlin Input Line Into Buffer
a579 42361 crunch Tokenise Input Buffer
a613 42515 fndlin Search for Line Number
a642 42562 scrtch Perform [new]
a65e 42590 clear Perform [clr]
a68e 42638 stxpt Reset TXTPTR
a69c 42652 list Perform [list]
a717 42775 qplop Handle LIST Character
a742 42818 for Perform [for]
a7ae 42926 newstt BASIC Warm Start
a7c4 42948 ckeol Check End of Program
a7e1 42977 gone Prepare to execute statement
a7ed 42989 gone3 Perform BASIC Keyword
a81d 43037 restor Perform [restore]
a82c 43052 stop Perform [stop], [end], break
a857 43095 cont Perform [cont]
a871 43121 run Perform [run]
a883 43139 gosub Perform [gosub]
a8a0 43168 goto Perform [goto]
a8d2 43218 return Perform [return]
a8f8 43256 data Perform [data]
a906 43270 datan Search for Next Statement / Line
a928 43304 if Perform [if]
a93b 43323 rem Perform [rem]
a94b 43339 ongoto Perform [on]
a96b 43371 linget Fetch linnum From BASIC
a9a5 43429 let Perform [let]
a9c4 43460 putint Assign Integer
a9d6 43478 ptflpt Assign Floating Point
a9d9 43481 putstr Assign String
a9e3 43491 puttim Assign TI$
aa2c 43564 getspt Add Digit to FAC#1
aa80 43648 printn Perform [print]#
aa86 43654 cmd Perform [cmd]
aa9a 43674 strdon Print String From Memory
aaa0 43680 print Perform [print]
aab8 43704 varop Output Variable
aad7 43735 crdo Output CR/LF
aae8 43752 comprt Handle comma, TAB(, SPC(
ab1e 43806 strout Output String
ab3b 43835 outspc Output Format Character
ab4d 43853 doagin Handle Bad Data
ab7b 43899 get Perform [get]
aba5 43941 inputn Perform [input#]
abbf 43967 input Perform [input]
abea 44010 bufful Read Input Buffer
abf9 44025 qinlin Do Input Prompt
ac06 44038 read Perform [read]
ac35 44085 rdget General Purpose Read Routine
acfc 44284 exint Input Error Messages TEXT
ad1e 44318 next Perform [next]
ad61 44385 donext Check Valid Loop
ad8a 44426 frmnum Confirm Result
ad9e 44446 frmevl Evaluate Expression in Text
ae83 44675 eval Evaluate Single Term
aea8 44712 pival Constant - pi DATA
aead 44717 qdot Continue Expression
aef1 44785 parchk Expression in Brackets
aef7 44791 chkcls Confirm Character
aef7 44791 - -test ')'-
aefa 44794 - -test '('-
aefd 44797 - -test comma-
af08 44808 synerr Output ?SYNTAX Error
af0d 44813 domin Set up NOT Function
af14 44820 rsvvar Identify Reserved Variable
af28 44840 isvar Search for Variable
af48 44872 tisasc Convert TI to ASCII String
afa7 44967 isfun Identify Function Type
afb1 44977 strfun Evaluate String Function
afd1 45009 numfun Evaluate Numeric Function
afe6 45030 orop Perform [or], [and]
b016 45078 dorel Perform <, =, >
b01b 45083 numrel Numeric Comparison
b02e 45102 strrel String Comparison
b07e 45182 dim Perform [dim]
b08b 45195 ptrget Identify Variable
b0e7 45287 ordvar Locate Ordinary Variable
b11d 45341 notfns Create New Variable
b128 45352 notevl Create Variable
b194 45460 aryget Allocate Array Pointer Space
b1a5 45477 n32768 Constant 32768 in Flpt DATA
b1aa 45482 facinx FAC#1 to Integer in (AC/YR)
b1b2 45490 intidx Evaluate Text for Integer
b1bf 45503 ayint FAC#1 to Positive Integer
b1d1 45521 isary Get Array Parameters
b218 45592 fndary Find Array
b245 45637 bserr ?BAD SUBSCRIPT/?ILLEGAL QUANTITY
b261 45665 notfdd Create Array
b30e 45838 inlpn2 Locate Element in Array
b34c 45900 umult Number of Bytes in Subscript
b37d 45949 fre Perform [fre]
b391 45969 givayf Convert Integer in (AC/YR) to Flpt
b39e 45982 pos Perform [pos]
b3a6 45990 errdir Confirm Program Mode
b3e1 46049 getfnm Check Syntax of FN
b3f4 46068 fndoer Perform [fn]
b465 46181 strd Perform [str$]
b487 46215 strlit Set Up String
b4d5 46293 putnw1 Save String Descriptor
b4f4 46324 getspa Allocate Space for String
b526 46374 garbag Garbage Collection
b5bd 46525 dvars Search for Next String
b606 46598 grbpas Collect a String
b63d 46653 cat Concatenate Two Strings
b67a 46714 movins Store String in High RAM
b6a3 46755 frestr Perform String Housekeeping
b6db 46811 frefac Clean Descriptor Stack
b6ec 46828 chrd Perform [chr$]
b700 46848 leftd Perform [left$]
b72c 46892 rightd Perform [right$]
b737 46903 midd Perform [mid$]
b761 46945 pream Pull sTring Parameters
b77c 46972 len Perform [len]
b782 46978 len1 Exit String Mode
b78b 46987 asc Perform [asc]
b79b 47003 gtbytc Evaluate Text to 1 Byte in XR
b7ad 47021 val Perform [val]
b7b5 47029 strval Convert ASCII String to Flpt
b7eb 47083 getnum Get parameters for POKE/WAIT
b7f7 47095 getadr Convert FAC#1 to Integer in LINNUM
b80d 47117 peek Perform [peek]
b824 47140 poke Perform [poke]
b82d 47149 wait Perform [wait]
b849 47177 faddh Add 0.5 to FAC#1
b850 47184 fsub Perform Subtraction
b862 47202 fadd5 Normalise Addition
b867 47207 fadd Perform Addition
b947 47431 negfac 2's Complement FAC#1
b97e 47486 overr Output ?OVERFLOW Error
b983 47491 mulshf Multiply by Zero Byte
b9bc 47548 fone Table of Flpt Constants DATA
b9ea 47594 log Perform [log]
ba28 47656 fmult Perform Multiply
ba59 47705 mulply Multiply by a Byte
ba8c 47756 conupk Load FAC#2 From Memory
bab7 47799 muldiv Test Both Accumulators
bad4 47828 mldvex Overflow / Underflow
bae2 47842 mul10 Multiply FAC#1 by 10
baf9 47865 tenc Constant 10 in Flpt DATA
bafe 47870 div10 Divide FAC#1 by 10
bb07 47879 fdiv Divide FAC#2 by Flpt at (AC/YR)
bb0f 47887 fdivt Divide FAC#2 by FAC#1
bba2 48034 movfm Load FAC#1 From Memory
bbc7 48071 mov2f Store FAC#1 in Memory
bbfc 48124 movfa Copy FAC#2 into FAC#1
bc0c 48140 movaf Copy FAC#1 into FAC#2
bc1b 48155 round Round FAC#1
bc2b 48171 sign Check Sign of FAC#1
bc39 48185 sgn Perform [sgn]
bc58 48216 abs Perform [abs]
bc5b 48219 fcomp Compare FAC#1 With Memory
bc9b 48283 qint Convert FAC#1 to Integer
bccc 48332 int Perform [int]
bcf3 48371 fin Convert ASCII String to a Number in FAC#1
bdb3 48563 n0999 String Conversion Constants DATA
bdc2 48578 inprt Output 'IN' and Line Number
bddd 48605 fout Convert FAC#1 to ASCII String
be68 48744 foutim Convert TI to String
bf11 48913 fhalf Table of Constants DATA
bf71 49009 sqr Perform [sqr]
bf7b 49019 fpwrt Perform power ($)
bfb4 49076 negop Negate FAC#1
bfbf 49087 logeb2 Table of Constants DATA
bfed 49133 exp Perform [exp]
C000-CFFF 49152 4 KB RAM.
D000-DFFF 53248 Input/Output Devices and Colour RAM or
4 KB RAM or Character ROM.
D000-D02E 53248 6566 Video Interface Chip, VIC II.
D000-D02E 53248-54271 MOS 6566 VIDEO INTERFACE CONTROLLER (VIC)
D000 53248 Sprite O X Pos
D001 53249 Sprite O Y Pos
D002 53250 Sprite 1 X Pos
D003 53251 Sprite 1 Y Pos
D004 53252 Sprite 2 X Pos
D005 53253 Sprite 2 Y Pos
D006 53254 Sprite 3 X Pos
D007 53255 Sprite 3 Y Pos
D008 53256 Sprite 4 X Pos
D009 53257 Sprite 4 Y Pos
D00A 53258 Sprite 5 X Pos
D00B 53259 Sprite 5 Y Pos
D00C 53260 Sprite 6 X Pos
D00D 53261 Sprite 6 Y Pos
D00E 53262 Sprite 7 X Pos
D00F 53263 Sprite 7 Y Pos
D010 53264 Sprites 0-7 X Pos (msb of X coord.)
D011 53265 VIC Control Register
7 Raster Compare: (Bit 8) See 53266
6 Extended Color Text Mode 1 = Enable
5 Bit Map Mode. 1 = Enable
4 Blank Screen to Border Color: O = Blank
3 Select 24/25 Row Text Display: 1 = 25 Rows
2-0 Smooth Scroll to Y Dot-Position (0-7)
D012 53266 Read Raster / Write Raster Value for Compare IRQ
D013 53267 Light-Pen Latch X Pos
D014 53268 Light-Pen Latch Y Pos
D015 53269 Sprite display Enable: 1 = Enable
D016 53270 VIC Control Register
7-6 Unused
5 ALWAYS SET THIS BIT TO 0 !
4 Multi-Color Mode: 1 = Enable (Text or Bit-Map)
3 Select 38/40 Column Text Display: 1 = 40 Cols
2-0 Smooth Scroll to X Pos
D017 53271 Sprites O-7 Expand 2x Vertical (Y)
D018 53272 VIC Memory Control Register
7-4 Video Matrix Base Address (inside VIC)
3-1 Character Dot-Data Base Address (inside VIC)
0 Select upper/lower Character Set
D019 53273 VIC Interrupt Flag Register (Bit = 1: IRQ Occurred)
7 Set on Any Enabled VIC IRQ Condition
3 Light-Pen Triggered IRQ Flag
2 Sprite to Sprite Collision IRQ Flag
1 Sprite to Background Collision IRQ Flag
0 Raster Compare IRQ Flag
D01A 53274 IRQ Mask Register: 1 = Interrupt Enabled
D01B 53275 Sprite to Background Display Priority: 1 = Sprite
D01C 53276 Sprites O-7 Multi-Color Mode Select: 1 = M.C.M.
D01D 53277 Sprites 0-7 Expand 2x Horizontal (X)
D01E 53278 Sprite to Sprite Collision Detect
D01F 53279 Sprite to Background Collision Detect
D020 53280 Border Color
D021 53281 Background Color O
D022 53282 Background Color 1
D023 53283 Background Color 2
D024 53284 Background Color 3
D025 53285 Sprite Multi-Color Register 0
D026 53286 Sprite Multi-Color Register 1
D027 53287 Sprite O Color
D028 53288 Sprite 1 Color
D029 53289 Sprite 2 Color
D02A 53290 Sprite 3 Color
D02B 53291 Sprite 4 Color
D02C 53292 Sprite 5 Color
D02D 53293 Sprite 6 Color
D02E 53294 Sprite 7 Color
D400-D41C 54272 6581 Sound Interface Device, SID.
D400-D7FF 54272-55295 MOS 6581 SOUND INTERFACE DEVICE (SID)
D400 54272 Voice 1: Frequency Control - Low-Byte
D401 54273 Voice 1: Frequency Control - High-Byte
D402 54274 Voice 1: Pulse Waveform Width - Low-Byte
D403 54275 7-4 Unused
3-0 Voice 1: Pulse Waveform Width - High-Nybble
D404 54276 Voice 1: Control Register
7 Select Random Noise Waveform, 1 = On
6 Select Pulse Waveform, 1 = On
5 Select Sawtooth Waveform, 1 = On
4 Select Triangle Waveform, 1 = On
3 Test Bit: 1 = Disable Oscillator 1
2 Ring Modulate Osc. 1 with Osc. 3 Output, 1 = On
1 Synchronize Osc. 1 with Osc. 3 Frequency, 1 = On
0 Gate Bit: 1 = Start Att/Dec/Sus, 0 = Start Release
D405 54277 Envelope Generator 1: Attack / Decay Cycle Control
7-4 Select Attack Cycle Duration: O-15
3-0 Select Decay Cycle Duration: 0-15
D406 54278 Envelope Generator 1: Sustain / Release Cycle Control
7-4 Select Sustain Cycle Duration: O-15
3-0 Select Release Cycle Duration: O-15
D407 54279 Voice 2: Frequency Control - Low-Byte
D408 54280 Voice 2: Frequency Control - High-Byte
D409 54281 Voice 2: Pulse Waveform Width - Low-Byte
D40A 54282 7-4 Unused
3-0 Voice 2: Pulse Waveform Width - High-Nybble
D40B 54283 Voice 2: Control Register
7 Select Random Noise Waveform, 1 = On
6 Select Pulse Waveform, 1 = On
5 Select Sawtooth Waveform, 1 = On
4 Select Triangle Waveform, 1 = On
3 Test Bit: 1 = Disable Oscillator 1
2 Ring Modulate Osc. 2 with Osc. 1 Output, 1 = On
1 Synchronize Osc. 2 with Osc. 1 Frequency, 1 = On
0 Gate Bit: 1 = Start Att/Dec/Sus, 0 = Start Release
D40C 54284 Envelope Generator 2: Attack / Decay Cycle Control
7-4 Select Attack Cycle Duration: O-15
3-0 Select Decay Cycle Duration: 0-15
D40D 54285 Envelope Generator 2: Sustain / Release Cycle Control
7-4 Select Sustain Cycle Duration: O-15
3-0 Select Release Cycle Duration: O-15
D40E 54286 Voice 3: Frequency Control - Low-Byte
D40F 54287 Voice 3: Frequency Control - High-Byte
D410 54288 Voice 3: Pulse Waveform Width - Low-Byte
D411 54289 7-4 Unused
3-0 Voice 3: Pulse Waveform Width - High-Nybble
D412 54290 Voice 3: Control Register
7 Select Random Noise Waveform, 1 = On
6 Select Pulse Waveform, 1 = On
5 Select Sawtooth Waveform, 1 = On
4 Select Triangle Waveform, 1 = On
3 Test Bit: 1 = Disable Oscillator 1
2 Ring Modulate Osc. 3 with Osc. 2 Output, 1 = On
1 Synchronize Osc. 3 with Osc. 2 Frequency, 1 = On
0 Gate Bit: 1 = Start Att/Dec/Sus, 0 = Start Release
D413 54291 Envelope Generator 3: Attac/Decay Cycle Control
7-4 Select Attack Cycle Duration: O-15
3-0 Select Decay Cycle Duration: 0-15
D414 54285 Envelope Generator 3: Sustain / Release Cycle Control
7-4 Select Sustain Cycle Duration: O-15
3-0 Select Release Cycle Duration: O-15
D415 54293 Filter Cutoff Frequency: Low-Nybble (Bits 2-O)
D416 54294 Filter Cutoff Frequency: High-Byte
D417 54295 Filter Resonance Control / Voice Input Control
7-4 Select Filter Resonance: 0-15
3 Filter External Input: 1 = Yes, 0 = No
2 Filter Voice 3 Output: 1 = Yes, 0 = No
Filter Voice 2 Output: 1 = Yes, 0 = No
0 Filter Voice 1 Output: 1 = Yes, 0 = No
D418 54296 Select Filter Mode and Volume
7 Cut-Off Voice 3 Output: 1 = Off, O = On
6 Select Filter High-Pass Mode: 1 = On
5 Select Filter Band-Pass Mode: 1 = On
4 Select Filter Low-Pass Mode: 1 = On
3-0 Select Output Volume: 0-15
D419 54297 Analog/Digital Converter: Game Paddle 1 (O-255)
D41A 54298 Analog/Digital Converter Game Paddle 2 (O-255)
D41B 54299 Oscillator 3 Random Number Generator
D41C 54230 Envelope Generator 3 Output
D500-D7FF 54528 SID Images.
D800-DBE7 55296 Colour RAM (Nybbles = 4 Bit RAM, LSB).
DBE8-DBFF 56296 Unused Nybbles.
DC00-DC0F 56320 6526 Complex Interface Adaptor, CIA.
DC00 56320 Data Port A (Keyboard, Joystick, Paddles, Light-Pen)
7-0 Write Keyboard Column Values for Keyboard Scan
7-6 Read Paddles on Port A / B (01 = Port A, 10 = Port B)
4 Joystick A Fire Button: 1 = Fire
3-2 Paddle Fire Buttons
3-0 Joystick A Direction (0-15)
DC01 56321 Data Port B (Keyboard, Joystick, Paddles): Game Port 1
7-0 Read Keyboard Row Values for Keyboard Scan
7 Timer B Toggle/Pulse Output
6 Timer A: Toggle/Pulse Output
4 Joystick 1 Fire Button: 1 = Fire
3-2 Paddle Fire Buttons
3-0 Joystick 1 Direction
DC02 56322 Data Direction Register - Port A (56320)
DC03 56323 Data Direction Register - Port B (56321)
DC04 56324 Timer A: Low-Byte
DC05 56325 Timer A: High-Byte
DC06 56326 Timer B: Low-Byte
DC07 56327 Timer B: High-Byte
DC08 56328 Time-of-Day Clock: 1/10 Seconds
DC09 56329 Time-of-Day Clock: Seconds
DC0A 56330 Time-of-Day Clock: Minutes
DC0B 56331 Time-of-Day Clock: Hours + AM/PM Flag (Bit 7)
DC0C 56332 Synchronous Serial I/O Data Buffer
DC0D 56333 CIA Interrupt Control Register (Read IRQs/Write Mask)
7 IRQ Flag (1 = IRQ Occurred) / Set-Clear Flag
4 FLAG1 IRQ (Cassette Read / Serial Bus SRQ Input)
3 Serial Port Interrupt
2 Time-of-Day Clock Alarm Interrupt
1 Timer B Interrupt
0 Timer A Interrupt
DC0E 56334 CIA Control Register A
7 Time-of-Day Clock Frequency: 1 = 50 Hz, 0 = 60 Hz
6 Serial Port I/O Mode Output, 0 = Input
5 Timer A Counts: 1 = CNT Signals, 0 = System 02 Clock
4 Force Load Timer A: 1 = Yes
3 Timer A Run Mode: 1 = One-Shot, 0 = Continuous
2 Timer A Output Mode to PB6: 1 = Toggle, 0 = Pulse
1 Timer A Output on PB6: 1 = Yes, 0 = No
0 Start/Stop Timer A: 1 = Start, 0 = Stop
DC0F 56335 CIA Control Register B
7 Set Alarm/TOD-Clock: 1 = Alarm, 0 = Clock
6-5 Timer B Mode Select:
00 = Count System 02 Clock Pulses
01 = Count Positive CNT Transitions
10 = Count Timer A Underflow Pulses
11 = Count Timer A Underflows While CNT Positive
4-0 Same as CIA Control Reg. A - for Timer B
DC00-DCFF 56320-56575 MOS 6526 Complex Interface Adapter (CIA) #1
DD00-DDFF 56576-56831 MOS 6526 Complex Interface Adapter (CIA) #2
DD00 56576 Data Port A (Serial Bus, RS-232, VIC Memory Control)
7 Serial Bus Data Input
6 Serial Bus Clock Pulse Input
5 Serial Bus Data Output
4 Serial Bus Clock Pulse Output
3 Serial Bus ATN Signal Output
2 RS-232 Data Output (User Port)
1-O VIC Chip System Memory Bank Select (Default = 11)
DD01 56577 Data Port B (User Port, RS-232)
7 User / RS-232 Data Set Ready
6 User / RS-232 Clear to Send
5 User
4 User / RS-232 Carrier Detect
3 User / RS-232 Ring Indicator
2 User / RS-232 Data Terminal Ready
1 User / RS-232 Request to Send
0 User / RS-232 Received Data
DD02 56578 Data Direction Register - Port A
DD03 56579 Data Direction Register - Port B
DD04 56580 Timer A: Low-Byte
DD05 56581 Timer A: High-Byte
DD06 56582 Timer B: Low-Byte
DD07 56583 Timer B: High-Byte
DD08 56584 Time-of-Day Clock: 1/10 Seconds
DD09 56585 Time-of-Day Clock: Seconds
DD0A 56586 Time-of-Day Clock: Minutes
DD0B 56587 Time-of-Day Clock: Hours + AM/PM Flag (Bit 7)
DD0C 56588 Synchronous Serial I/O Data Buffer
DD0D 56589 CIA Interrupt Control Register (Read NMls/Write Mask)
7 NMI Flag (1 = NMI Occurred) / Set-Clear Flag
4 FLAG1 NMI (User/RS-232 Received Data Input)
3 Serial Port Interrupt
1 Timer B Interrupt
0 Timer A Interrupt
DD0E 56590 CIA Control Register A
7 Time-of-Day Clock Frequency: 1 = 50 Hz, 0 = 60 Hz
6 Serial Port I/O Mode Output, 0 = Input
5 Timer A Counts: 1 = CNT Signals, 0 = System 02 Clock
4 Force Load Timer A: 1 = Yes
3 Timer A Run Mode: 1 = One-Shot, 0 = Continuous
2 Timer A Output Mode to PB6: 1 = Toggle, 0 = Pulse
1 Timer A Output on PB6: 1 = Yes, 0 = No
0 Start/Stop Timer A: 1 = Start, 0 = Stop
DD0F 56591 CIA Control Register B
7 Set Alarm/TOD-Clock: 1 = Alarm, 0 = Clock
6-5 Timer B Mode Select:
00 = Count System 02 Clock Pulses
01 = Count Positive CNT Transitions
10 = Count Timer A Underflow Pulses
11 = Count Timer A Underflows While CNT Positive
4-0 Same as CIA Control Reg. A - for Timer B
DEOO-DEFF 56832-57087 Reserved for Future I/O Expansion
DFOO-DFFF 57088-57343 Reserved for Future I/O Expansion
E000-FFFF 57344 BASIC (Part)/Kernal ROM or 8 KB RAM.
E000-E4FF 57344 BASIC ROM (Part) or RAM.
e000 57344 (exp continues) EXP continued From BASIC ROM
e043 57411 polyx Series Evaluation
e08d 57485 rmulc Constants for RND DATA
e097 57495 rnd Perform [rnd]
e0f9 57593 bioerr Handle I/O Error in BASIC
e10c 57612 bchout Output Character
e112 57618 bchin Input Character
e118 57624 bckout Set Up For Output
e11e 57630 bckin Set Up For Input
e124 57636 bgetin Get One Character
e12a 57642 sys Perform [sys]
e156 57686 savet Perform [save]
e165 57701 verfyt Perform [verify / load]
e1be 57790 opent Perform [open]
e1c7 57799 closet Perform [close]
e1d4 57812 slpara Get Parameters For LOAD/SAVE
e200 57856 combyt Get Next One Byte Parameter
e206 57862 deflt Check Default Parameters
e20e 57870 cmmerr Check For Comma
e219 57881 ocpara Get Parameters For OPEN/CLOSE
e264 57956 cos Perform [cos]
e26b 57963 sin Perform [sin]
e2b4 58036 tan Perform [tan]
e2e0 58080 pi2 Table of Trig Constants DATA
;e2e0 1.570796327 pi/2
;e2e5 6.28318531 pi*2
;e2ea 0.25
;e2ef #05 (counter)
;e2f0 -14.3813907
;e2f5 42.0077971
;e2fa -76.7041703
;e2ff 81.6052237
;e304 -41.3417021
;e309 6.28318531
e30e 58126 atn Perform [atn]
e33e 58174 atncon Table of ATN Constants DATA
;e33e #0b (counter)
;e3ef -0.000684793912
;e344 0.00485094216
;e349 -0.161117018
;e34e 0.034209638
;e353 -0.0542791328
;e358 0.0724571965
;e35d -0.0898023954
;e362 0.110932413
;e367 -0.142839808
;e36c 0.19999912
;e371 -0.333333316
;e376 1.00
e37b 58235 bassft BASIC Warm Start [RUNSTOP-RESTORE]
e394 58260 init BASIC Cold Start
e3a2 58274 initat CHRGET For Zero-page
e3ba 58298 rndsed RND Seed For zero-page DATA
;e3b2 0.811635157
e3bf 58303 initcz Initialize BASIC RAM
e422 58402 initms Output Power-Up Message
e447 58439 bvtrs Table of BASIC Vectors (for 0300) WORD
e453 58451 initv Initialize Vectors
e45f 58463 words Power-Up Message DATA
e4ad 58541 - Patch for BASIC Call to CHKOUT
e4b7 58551 - Unused Bytes For Future Patches EMPTY
e4da 58586 - Reset Character Colour
e4e0 58592 - Pause After Finding Tape File
e4ec 58604 - RS-232 Timing Table -- PAL DATA
E500-FFFF 58624 Kernal ROM or RAM.
e500 58624 iobase Get I/O Address
e505 58629 screen Get Screen Size
e50a 58634 plot Put / Get Row And Column
e518 58648 cint1 Initialize I/O
e544 58692 - Clear Screen
e566 58726 - Home Cursor
e56c 58732 - Set Screen Pointers
e59a 58778 - Set I/O Defaults (Unused Entry)
e5a0 58784 - Set I/O Defaults
e5b4 58804 lp2 Get Character From Keyboard Buffer
e5ca 58826 - Input From Keyboard
e632 58930 - Input From Screen or Keyboard
e684 59012 - Quotes Test
e691 59025 - Set Up Screen Print
e6b6 59062 - Advance Cursor
e6ed 59117 - Retreat Cursor
e701 59137 - Back on to Previous Line
e716 59158 - Output to Screen
e72a 59178 - -unshifted characters-
e7d4 59348 - -shifted characters-
e87c 59516 - Go to Next Line
e891 59537 - Output
e8a1 59553 - Check Line Decrement
e8b3 59571 - Check Line Increment
e8cb 59595 - Set Colour Code
e8da 59610 - Colour Code Table
e8ea 59626 - Scroll Screen
e965 59749 - Open A Space On The Screen
e9c8 59848 - Move A Screen Line
e9e0 59872 - Syncronise Colour Transfer
e9f0 59888 - Set Start of Line
e9ff 59903 - Clear Screen Line
ea13 59923 - Print To Screen
ea24 59940 - Syncronise Colour Pointer
ea31 59953 - Main IRQ Entry Point
ea87 60039 scnkey Scan Keyboard
eadd 60125 - Process Key Image
eb79 60281 - Pointers to Keyboard decoding tables WORD
eb81 60289 - Keyboard 1 -- unshifted DATA
ebc2 60354 - Keyboard 2 -- Shifted DATA
ec03 60419 - Keyboard 3 -- Commodore DATA
ec44 60484 - Graphics/Text Control
ec78 60536 - Keyboard 4 -- Control DATA
ecb9 60601 - Video Chip Setup Table DATA
ece7 60647 - Shift-Run Equivalent
ecf0 60656 - Low Byte Screen Line Addresses DATA
ed09 60681 talk Send TALK Command on Serial Bus
ed0c 60684 listn Send LISTEN Command on Serial Bus
ed40 60736 - Send Data On Serial Bus
edad 60845 - Flag Errors
edad 60845 - Status #80 - device not present
edb0 60848 - Status #03 - write timeout
edb9 60857 second Send LISTEN Secondary Address
edbe 60862 - Clear ATN
edc7 60871 tksa Send TALK Secondary Address
edcc 60876 - Wait For Clock
eddd 60893 ciout Send Serial Deferred
edef 60911 untlk Send UNTALK / UNLISTEN
ee13 60947 acptr Receive From Serial Bus
ee85 61061 - Serial Clock On
ee8e 61070 - Serial Clock Off
ee97 61079 - Serial Output 1
eea0 61088 - Serial Output 0
eea9 61097 - Get Serial Data And Clock In
eeb3 61107 - Delay 1 ms
eebb 61115 - RS-232 Send
ef06 61190 - Send New RS-232 Byte
ef2e 61230 - 'No DSR' / 'No CTS' Error
ef39 61241 - Disable Timer
ef4a 61258 - Compute Bit Count
ef59 61273 - RS-232 Receive
ef7e 61310 - Set Up To Receive
ef90 61328 - Process RS-232 Byte
efe1 61409 - Submit to RS-232
f00d 61453 - No DSR (Data Set Ready) Error
f017 61463 - Send to RS-232 Buffer
f04d 61517 - Input From RS-232
f086 61574 - Get From RS-232
f0a4 61604 - Serial Bus Idle
f0bd 61629 - Table of Kernal I/O Messages DATA
f12b 61739 - Print Message if Direct
f12f 61743 - Print Message
f13e 61758 getin Get a byte
f157 61783 chrin Input a byte
f199 61849 - Get From Tape / Serial / RS-232
f1ca 61898 chrout Output One Character
f20e 61966 chkin Set Input Device
f250 62032 chkout Set Output Device
f291 62097 close Close File
f30f 62223 - Find File
f31f 62239 - Set File values
f32f 62255 clall Abort All Files
f333 62259 clrchn Restore Default I/O
f34a 62282 open Open File
f3d5 62421 - Send Secondary Address
f409 62473 - Open RS-232
f49e 62622 load Load RAM
f4b8 62648 - Load File From Serial Bus
f533 62771 - Load File From Tape
f5af 62927 - Print "SEARCHING"
f5c1 62913 - Print Filename
f5d2 62930 - Print "LOADING / VERIFYING"
f5dd 62941 save Save RAM
f5fa 62970 - Save to Serial Bus
f659 63065 - Save to Tape
f68f 63119 - Print "SAVING"
f69b 63131 udtim Bump Clock
f6dd 63197 rdtim Get Time
f6e4 63204 settim Set Time
f6ed 63213 stop Check STOP Key
f6fb 63227 - Output I/O Error Messages
f6fb 63227 - 'too many files'
f6fe 63230 - 'file open'
f701 63233 - 'file not open'
f704 63236 - 'file not found'
f707 63239 - 'device not present'
f70a 63242 - 'not input file'
f70d 63245 - 'not output file'
f710 63248 - 'missing filename'
f713 63251 - 'illegal device number'
f72d 63277 - Find Any Tape Header
f76a 63338 - Write Tape Header
f7d0 63440 - Get Buffer Address
f7d7 63447 - Set Buffer Stat / End Pointers
f7ea 63466 - Find Specific Tape Header
f80d 63501 - Bump Tape Pointer
f817 63511 - Print "PRESS PLAY ON TAPE"
f82e 63534 - Check Tape Status
f838 63544 - Print "PRESS RECORD..."
f841 63553 - Initiate Tape Read
f864 63588 - Initiate Tape Write
f875 63605 - Common Tape Code
f8d0 63696 - Check Tape Stop
f8e2 63714 - Set Read Timing
f92c 63788 - Read Tape Bits
fa60 64096 - Store Tape Characters
fb8e 64398 - Reset Tape Pointer
fb97 64407 - New Character Setup
fba6 64422 - Send Tone to Tape
fbc8 64456 - Write Data to Tape
fbcd 64461 - IRQ Entry Point
fc57 64599 - Write Tape Leader
fc93 64659 - Restore Normal IRQ
fcb8 64696 - Set IRQ Vector
fcca 64714 - Kill Tape Motor
fcd1 64721 - Check Read / Write Pointer
fcdb 64731 - Bump Read / Write Pointer
fce2 64738 - Power-Up RESET Entry
fd02 64770 - Check For 8-ROM
fd12 64786 - 8-ROM Mask '80CBM' DATA
fd15 64789 restor Restore Kernal Vectors (at 0314)
fd1a 64794 vector Change Vectors For User
fd30 64816 - Kernal Reset Vectors WORD
fd50 64848 ramtas Initialise System Constants
fd9b 64923 - IRQ Vectors For Tape I/O WORD
fda3 64931 ioinit Initialise I/O
fddd 64989 - Enable Timer
fdf9 65017 setnam Set Filename
fe00 65024 setlfs Set Logical File Parameters
fe07 65031 readst Get I/O Status Word
fe18 65048 setmsg Control OS Messages
fe21 65057 settmo Set IEEE Timeout
fe25 65061 memtop Read / Set Top of Memory
fe34 65076 membot Read / Set Bottom of Memory
fe43 65091 - NMI Transfer Entry
fe66 65126 - Warm Start Basic [BRK]
febc 65212 - Exit Interrupt
fec2 65218 - RS-232 Timing Table - NTSC DATA
fed6 65238 - NMI RS-232 In
ff07 65287 - NMI RS-232 Out
ff43 65347 - Fake IRQ Entry
ff48 65352 - IRQ Entry
ff5b 65371 cint Initialize screen editor
ff80 65408 - Kernal Version Number [03] DATA
APPENDIX B
----------
; ------
;
; Commodore 64 ROM Memory Map
;
; BASIC interpreter ROM ($A000 - $BFFF)
;
; label address type comments
restart = $a000
stmdsp = $a00c
fundsp = $a052
optab = $a080
reslst = $a09e
msclst = $a129
oplist = $a140
funlst = $a14d
errtab = $a19e
errptr = $a328
okk = $a364
fndfor = $a38a
bltu = $a3b8
getstk = $a3fb
reason = $a408
omerr = $a435
error = $a437
errfin = $a469
ready = $a474
main = $a480
main1 = $a49c
inslin = $a4a2
linkprg = $a533
inlin = $a560
crunch = $a579
fndlin = $a613
scrtch = $a642
clear = $a65e
stxpt = $a68e
list = $a69c
qplop = $a717
for = $a742
newstt = $a7ae
ckeol = $a7c4
gone = $a7e1
gone3 = $a7ed
restor = $a81d
stop = $a82c
cont = $a857
run = $a871
gosub = $a883
goto = $a8a0
return = $a8d2
data = $a8f8
datan = $a906
if = $a928
rem = $a93b
ongoto = $a94b
linget = $a96b
let = $a9a5
putint = $a9c4
ptflpt = $a9d6
putstr = $a9d9
puttim = $a9e3
getspt = $aa2c
printn = $aa80
cmd = $aa86
strdon = $aa9a
print = $aaa0
varop = $aab8
crdo = $aad7
comprt = $aae8
strout = $ab1e
outspc = $ab3b
doagin = $ab4d
get = $ab7b
inputn = $aba5
input = $abbf
bufful = $abea
qinlin = $abf9
read = $ac06
rdget = $ac35
exint = $acfc
next = $ad1e
donext = $ad61
frmnum = $ad8a
frmevl = $ad9e
eval = $ae83
pival = $aea8
qdot = $aead
parchk = $aef1
chkcls = $aef7
synerr = $af08
domin = $af0d
rsvvar = $af14
isvar = $af28
tisasc = $af48
isfun = $afa7
strfun = $afb1
numfun = $afd1
orop = $afe6
dorel = $b016
numrel = $b01b
strrel = $b02e
dim = $b07e
ptrget = $b08b
ordvar = $b0e7
isletc = $b113
notfns = $b11d
notevl = $b128
aryget = $b194
n32768 = $b1a5 data
facinx = $b1aa
intidx = $b1b2
ayint = $b1bf
isary = $b1d1
fndary = $b218
bserr = $b245
notfdd = $b261
inlpn2 = $b30e
umult = $b34c
fre = $b37d
givayf = $b391
pos = $b39e
errdir = $b3a6
def = $b3b3
getfnm = $b3e1
fndoer = $b3f4
strd = $b465
strlit = $b487
putnw1 = $b4d5
getspa = $b4f4
garbag = $b526
dvars = $b5bd
grbpas = $b606
cat = $b63d
movins = $b67a
frestr = $b6a3
frefac = $b6db
chrd = $b6ec
leftd = $b700
rightd = $b72c
midd = $b737
pream = $b761
len = $b77c
len1 = $b782
asc = $b78b
gtbytc = $b79b
val = $b7ad
strval = $b7b5
getnum = $b7eb
getadr = $b7f7
peek = $b80d
poke = $b824
wait = $b82d
faddh = $b849
fsub = $b850
fadd5 = $b862
fadd = $b867
negfac = $b947
overr = $b97e
mulshf = $b983
fone = $b9bc data
log = $b9ea
fmult = $ba28
mulply = $ba59
conupk = $ba8c
muldiv = $bab7
mldvex = $bad4
mul10 = $bae2
tenc = $baf9 data
div10 = $bafe
fdiv = $bb07
fdivt = $bb0f
movfm = $bba2
mov2f = $bbc7
movfa = $bbfc
movaf = $bc0c
round = $bc1b
sign = $bc2b
sgn = $bc39
abs = $bc58
fcomp = $bc5b
qint = $bc9b
int = $bccc
fin = $bcf3
n0999 = $bdb3 data
inprt = $bdc2
fout = $bddd
foutim = $be68
fhalf = $bf11 data
sqr = $bf71
fpwrt = $bf7b
negop = $bfb4
logeb2 = $bfbf data
exp = $bfed
;
;
; C64 KERNEL ROM
;
(exp = $e000
polyx = $e043
rmulc = $e08d data
rnd = $e097
bioerr = $e0f9
bchout = $e10c
bchin = $e112
bckout = $e118
bckin = $e11e
bgetin = $e124
sys = $e12a
savet = $e156
verfyt = $e165
opent = $e1be
closet = $e1c7
slpara = $e1d4
combyt = $e200
deflt = $e206
cmmerr = $e20e
ocpara = $e219
cos = $e264
sin = $e26b
tan = $e2b4
pi2 = $e2e0 data
atn = $e30e
atncon = $e33e data
bassft = $e37b
init = $e394
initat = $e3a2
rndsed = $e3ba
initcz = $e3bf
initms = $e422
bvtrs = $e447 data
initv = $e453
words = $e45f
- = $e4ad
- = $e4b7 illegal
- = $e4da
- = $e4e0
- = $e4ec data
iobase = $e500
screen = $e505
plot = $e50a
cint1 = $e518
- = $e544
- = $e566
- = $e56c
= ;
- = $e59a
lp2 = $e5b4
- = $e5ca
- = $e632
- = $e684
- = $e691
- = $e6b6
- = $e6ed
- = $e701
- = $e716
- = $e87c
- = $e891
- = $e8a1
- = $eacb
- = $e8da
- = $e8ea
- = $e965
- = $e9c8
- = $e9e0
- = $e9f0
- = $e9ff
- = $ea13
- = $ea24
- = $ea31
scnkey = $ea87
- = $eadd data
- = $eb79 data
- = $eb81 data
- = $ebc2 data
- = $ec03
- = $ec44 data
- = $ec78 data
- = $ecb9
- = $ece7 data
- = $ecf0
talk = $ed09
- = $ed40
- = $edad
second = $edb9
- = $edbe
tksa = $edc7
- = $edcc
ciout = $eddd
untlk = $edef
acptr = $ee13
- = $ee85
- = $ee8e
- = $ee97
- = $eea0
- = $eea9
- = $eeb3
- = $eebb
- = $ef06
- = $ef2e
- = $ef39
- = $ef4a
- = $ef59
- = $ef7e
- = $ef90
- = $efe1
- = $f00d
- = $f017
- = $f04d
- = $f086
- = $f0a4
- = $f0bd
- = $f128
getin = $f13e
chrin = $f157
- = $f199
chrout = $f1ca
chkin = $f20e
chkout = $f250
close = $f291
- = $f30f
- = $f31f
clall = $f32f
clrchn = $f333
open = $f34a
- = $f3d5
- = $f409
load = $f49e
;
;--------------
;
save = $f5dd
udtim = $f69b
rdtim = $f6dd
settim = $f6e4
stop = $f6ed
restor = $fd15
vector = $fd1a
ramtas = $fd50
ioinit = $fda3
setnam = $fdf9
setlfs = $fe00
readst = $fe07
setmsg = $fe18
settmo = $fe21
memtop = $fe25
membot = $fe34
cint = $fe58
APPENDIX C
----------
;
;
; C64 KERNEL call addresses
;
acptr = $ffa5
chkin = $ffc6
chkout = $ffc9
chrin = $ffcf
chrout = $ffd2
ciout = $ffa8
cint = $ff81
clall = $ffe7
close = $ffc3
clrchn = $ffcc
getin = $ffe4
iobase = $fff3
ioinit = $ff84
listen = $ffb1
load = $ffd5
membot = $ff9c
memtop = $ff99
open = $ffc0
plot = $fff0
ramtas = $ff87
rdtim = $ffde
readst = $ffb7
restor = $ff8a
save = $ffd8
scnkey = $ff9f
screen = $ffed
second = $ff93
setlfs = $ffba
setmsg = $ff90
setnam = $ffbd
settim = $ffdb
settmo = $ffa2
stop = $ffe1
talk = $ffb4
tksa = $ff96
udtim = $ffea
unlsn = $ffae
untlk = $ffab
vector = $ff8d
;
APPENDIX D
----------
OPCODES::
--------------
REPRODUCED FROM C=HACKING MAGAZINE..
6502 Opcodes and Quasi-Opcodes.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The following table lists all of the available opcodes on the 65xx line of
micro-processors (such as the 6510 on the C=64 and the 8502 on the C=128)
-----------------------------------------------------------------------------
Std Mnemonic Hex Value Description Addressing Mode Bytes/Time
* BRK $00 Stack <- PC, PC <- ($fffe) (Immediate) 1/7
* ORA $01 A <- (A) V M (Ind,X) 6/2
JAM $02 [locks up machine] (Implied) 1/-
SLO $03 M <- (M >> 1) + A + C (Ind,X) 2/8
NOP $04 [no operation] (Z-Page) 2/3
* ORA $05 A <- (A) V M (Z-Page) 2/3
* ASL $06 C <- A7, A <- (A) << 1 (Z-Page) 2/5
SLO $07 M <- (M >> 1) + A + C (Z-Page) 2/5
* PHP $08 Stack <- (P) (Implied) 1/3
* ORA $09 A <- (A) V M (Immediate) 2/2
* ASL $0A C <- A7, A <- (A) << 1 (Accumalator) 1/2
ANC $0B A <- A /\ M, C=~A7 (Immediate) 1/2
NOP $0C [no operation] (Absolute) 3/4
* ORA $0D A <- (A) V M (Absolute) 3/4
* ASL $0E C <- A7, A <- (A) << 1 (Absolute) 3/6
SLO $0F M <- (M >> 1) + A + C (Absolute) 3/6
* BPL $10 if N=0, PC = PC + offset (Relative) 2/2'2
* ORA $11 A <- (A) V M ((Ind),Y) 2/5'1
JAM $12 [locks up machine] (Implied) 1/-
SLO $13 M <- (M >. 1) + A + C ((Ind),Y) 2/8'5
NOP $14 [no operation] (Z-Page,X) 2/4
* ORA $15 A <- (A) V M (Z-Page,X) 2/4
* ASL $16 C <- A7, A <- (A) << 1 (Z-Page,X) 2/6
SLO $17 M <- (M >> 1) + A + C (Z-Page,X) 2/6
* CLC $18 C <- 0 (Implied) 1/2
* ORA $19 A <- (A) V M (Absolute,Y) 3/4'1
NOP $1A [no operation] (Implied) 1/2
SLO $1B M <- (M >> 1) + A + C (Absolute,Y) 3/7
NOP $1C [no operation] (Absolute,X) 2/4'1
* ORA $1D A <- (A) V M (Absolute,X) 3/4'1
* ASL $1E C <- A7, A <- (A) << 1 (Absolute,X) 3/7
SLO $1F M <- (M >> 1) + A + C (Absolute,X) 3/7
* JSR $20 Stack <- PC, PC <- Address (Absolute) 3/6
* AND $21 A <- (A) /\ M (Ind,X) 2/6
JAM $22 [locks up machine] (Implied) 1/-
RLA $23 M <- (M << 1) /\ (A) (Ind,X) 2/8
* BIT $24 Z <- ~(A /\ M) N<-M7 V<-M6 (Z-Page) 2/3
* AND $25 A <- (A) /\ M (Z-Page) 2/3
* ROL $26 C <- A7 & A <- A << 1 + C (Z-Page) 2/5
RLA $27 M <- (M << 1) /\ (A) (Z-Page) 2/5'5
* PLP $28 A <- (Stack) (Implied) 1/4
* AND $29 A <- (A) /\ M (Immediate) 2/2
* ROL $2A C <- A7 & A <- A << 1 + C (Accumalator) 1/2
ANC $2B A <- A /\ M, C <- ~A7 (Immediate9 1/2
* BIT $2C Z <- ~(A /\ M) N<-M7 V<-M6 (Absolute) 3/4
* AND $2D A <- (A) /\ M (Absolute) 3/4
* ROL $2E C <- A7 & A <- A << 1 + C (Absolute) 3/6
RLA $2F M <- (M << 1) /\ (A) (Absolute) 3/6'5
* BMI $30 if N=1, PC = PC + offset (Relative) 2/2'2
* AND $31 A <- (A) /\ M ((Ind),Y) 2/5'1
JAM $32 [locks up machine] (Implied) 1/-
RLA $33 M <- (M << 1) /\ (A) ((Ind),Y) 2/8'5
NOP $34 [no operation] (Z-Page,X) 2/4
* AND $35 A <- (A) /\ M (Z-Page,X) 2/4
* ROL $36 C <- A7 & A <- A << 1 + C (Z-Page,X) 2/6
RLA $37 M <- (M << 1) /\ (A) (Z-Page,X) 2/6'5
* SEC $38 C <- 1 (Implied) 1/2
* AND $39 A <- (A) /\ M (Absolute,Y) 3/4'1
NOP $3A [no operation] (Implied) 1/2
RLA $3B M <- (M << 1) /\ (A) (Absolute,Y) 3/7'5
NOP $3C [no operation] (Absolute,X) 3/4'1
* AND $3D A <- (A) /\ M (Absolute,X) 3/4'1
* ROL $3E C <- A7 & A <- A << 1 + C (Absolute,X) 3/7
RLA $3F M <- (M << 1) /\ (A) (Absolute,X) 3/7'5
* RTI $40 P <- (Stack), PC <-(Stack) (Implied) 1/6
* EOR $41 A <- (A) \-/ M (Ind,X) 2/6
JAM $42 [locks up machine] (Implied) 1/-
SRE $43 M <- (M >> 1) \-/ A (Ind,X) 2/8
NOP $44 [no operation] (Z-Page) 2/3
* EOR $45 A <- (A) \-/ M (Z-Page) 2/3
* LSR $46 C <- A0, A <- (A) >> 1 (Absolute,X) 3/7
SRE $47 M <- (M >> 1) \-/ A (Z-Page) 2/5
* PHA $48 Stack <- (A) (Implied) 1/3
* EOR $49 A <- (A) \-/ M (Immediate) 2/2
* LSR $4A C <- A0, A <- (A) >> 1 (Accumalator) 1/2
ASR $4B A <- [(A /\ M) >> 1] (Immediate) 1/2
* JMP $4C PC <- Address (Absolute) 3/3
* EOR $4D A <- (A) \-/ M (Absolute) 3/4
* LSR $4E C <- A0, A <- (A) >> 1 (Absolute) 3/6
SRE $4F M <- (M >> 1) \-/ A (Absolute) 3/6
* BVC $50 if V=0, PC = PC + offset (Relative) 2/2'2
* EOR $51 A <- (A) \-/ M ((Ind),Y) 2/5'1
JAM $52 [locks up machine] (Implied) 1/-
SRE $53 M <- (M >> 1) \-/ A ((Ind),Y) 2/8
NOP $54 [no operation] (Z-Page,X) 2/4
* EOR $55 A <- (A) \-/ M (Z-Page,X) 2/4
* LSR $56 C <- A0, A <- (A) >> 1 (Z-Page,X) 2/6
SRE $57 M <- (M >> 1) \-/ A (Z-Page,X) 2/6
* CLI $58 I <- 0 (Implied) 1/2
* EOR $59 A <- (A) \-/ M (Absolute,Y) 3/4'1
NOP $5A [no operation] (Implied) 1/2
SRE $5B M <- (M >> 1) \-/ A (Absolute,Y) 3/7
NOP $5C [no operation] (Absolute,X) 3/4'1
* EOR $5D A <- (A) \-/ M (Absolute,X) 3/4'1
SRE $5F M <- (M >> 1) \-/ A (Absolute,X) 3/7
* RTS $60 PC <- (Stack) (Implied) 1/6
* ADC $61 A <- (A) + M + C (Ind,X) 2/6
JAM $62 [locks up machine] (Implied) 1/-
RRA $63 M <- (M >> 1) + (A) + C (Ind,X) 2/8'5
NOP $64 [no operation] (Z-Page) 2/3
* ADC $65 A <- (A) + M + C (Z-Page) 2/3
* ROR $66 C<-A0 & A<- (A7=C + A>>1) (Z-Page) 2/5
RRA $67 M <- (M >> 1) + (A) + C (Z-Page) 2/5'5
* PLA $68 A <- (Stack) (Implied) 1/4
* ADC $69 A <- (A) + M + C (Immediate) 2/2
* ROR $6A C<-A0 & A<- (A7=C + A>>1) (Accumalator) 1/2
ARR $6B A <- [(A /\ M) >> 1] (Immediate) 1/2'5
* JMP $6C PC <- Address (Indirect) 3/5
* ADC $6D A <- (A) + M + C (Absolute) 3/4
* ROR $6E C<-A0 & A<- (A7=C + A>>1) (Absolute) 3/6
RRA $6F M <- (M >> 1) + (A) + C (Absolute) 3/6'5
* BVS $70 if V=1, PC = PC + offset (Relative) 2/2'2
* ADC $71 A <- (A) + M + C ((Ind),Y) 2/5'1
JAM $72 [locks up machine] (Implied) 1/-
RRA $73 M <- (M >> 1) + (A) + C ((Ind),Y) 2/8'5
NOP $74 [no operation] (Z-Page,X) 2/4
* ADC $75 A <- (A) + M + C (Z-Page,X) 2/4
* ROR $76 C<-A0 & A<- (A7=C + A>>1) (Z-Page,X) 2/6
RRA $77 M <- (M >> 1) + (A) + C (Z-Page,X) 2/6'5
* SEI $78 I <- 1 (Implied) 1/2
* ADC $79 A <- (A) + M + C (Absolute,Y) 3/4'1
NOP $7A [no operation] (Implied) 1/2
RRA $7B M <- (M >> 1) + (A) + C (Absolute,Y) 3/7'5
NOP $7C [no operation] (Absolute,X) 3/4'1
* ADC $7D A <- (A) + M + C (Absolute,X) 3/4'1
* ROR $7E C<-A0 & A<- (A7=C + A>>1) (Absolute,X) 3/7
RRA $7F M <- (M >> 1) + (A) + C (Absolute,X) 3/7'5
NOP $80 [no operation] (Immediate) 2/2
* STA $81 M <- (A) (Ind,X) 2/6
NOP $82 [no operation] (Immediate) 2/2
SAX $83 M <- (A) /\ (X) (Ind,X) 2/6
* STY $84 M <- (Y) (Z-Page) 2/3
* STA $85 M <- (A) (Z-Page) 2/3
* STX $86 M <- (X) (Z-Page) 2/3
SAX $87 M <- (A) /\ (X) (Z-Page) 2/3
* DEY $88 Y <- (Y) - 1 (Implied) 1/2
NOP $89 [no operation] (Immediate) 2/2
* TXA $8A A <- (X) (Implied) 1/2
ANE $8B M <-[(A)\/$EE] /\ (X)/\(M) (Immediate) 2/2^4
* STY $8C M <- (Y) (Absolute) 3/4
* STA $8D M <- (A) (Absolute) 3/4
* STX $8E M <- (X) (Absolute) 3/4
SAX $8F M <- (A) /\ (X) (Absolute) 3/4
* BCC $90 if C=0, PC = PC + offset (Relative) 2/2'2
* STA $91 M <- (A) ((Ind),Y) 2/6
JAM $92 [locks up machine] (Implied) 1/-
SHA $93 M <- (A) /\ (X) /\ (PCH+1) (Absolute,X) 3/6'3
* STY $94 M <- (Y) (Z-Page,X) 2/4
* STA $95 M <- (A) (Z-Page,X) 2/4
SAX $97 M <- (A) /\ (X) (Z-Page,Y) 2/4
* STX $96 M <- (X) (Z-Page,Y) 2/4
* TYA $98 A <- (Y) (Implied) 1/2
* STA $99 M <- (A) (Absolute,Y) 3/5
* TXS $9A S <- (X) (Implied) 1/2
SHS $9B X <- (A) /\ (X), S <- (X) (Absolute,Y) 3/5
M <- (X) /\ (PCH+1)
SHY $9C M <- (Y) /\ (PCH+1) (Absolute,Y) 3/5'3
* STA $9D M <- (A) (Absolute,X) 3/5
SHX $9E M <- (X) /\ (PCH+1) (Absolute,X) 3/5'3
SHA $9F M <- (A) /\ (X) /\ (PCH+1) (Absolute,Y) 3/5'3
* LDY $A0 Y <- M (Immediate) 2/2
* LDA $A1 A <- M (Ind,X) 2/6
* LDX $A2 X <- M (Immediate) 2/2
LAX $A3 A <- M, X <- M (Ind,X) 2/6
* LDY $A4 Y <- M (Z-Page) 2/3
* LDA $A5 A <- M (Z-Page) 2/3
* LDX $A6 X <- M (Z-Page) 2/3
LAX $A7 A <- M, X <- M (Z-Page) 2/3
* TAY $A8 Y <- (A) (Implied) 1/2
* LDA $A9 A <- M (Immediate) 2/2
* TAX $AA X <- (A) (Implied) 1/2
LXA $AB X04 <- (X04) /\ M04 (Immediate) 1/2
A04 <- (A04) /\ M04
* LDY $AC Y <- M (Absolute) 3/4
* LDA $AD A <- M (Absolute) 3/4
* LDX $AE X <- M (Absolute) 3/4
LAX $AF A <- M, X <- M (Absolute) 3/4
* BCS $B0 if C=1, PC = PC + offset (Relative) 2/2'2
* LDA $B1 A <- M ((Ind),Y) 2/5'1
JAM $B2 [locks up machine] (Implied) 1/-
LAX $B3 A <- M, X <- M ((Ind),Y) 2/5'1
* LDY $B4 Y <- M (Z-Page,X) 2/4
* LDA $B5 A <- M (Z-Page,X) 2/4
* LDX $B6 X <- M (Z-Page,Y) 2/4
LAX $B7 A <- M, X <- M (Z-Page,Y) 2/4
* CLV $B8 V <- 0 (Implied) 1/2
* LDA $B9 A <- M (Absolute,Y) 3/4'1
* TSX $BA X <- (S) (Implied) 1/2
LAE $BB X,S,A <- (S /\ M) (Absolute,Y) 3/4'1
* LDY $BC Y <- M (Absolute,X) 3/4'1
* LDA $BD A <- M (Absolute,X) 3/4'1
* LDX $BE X <- M (Absolute,Y) 3/4'1
LAX $BF A <- M, X <- M (Absolute,Y) 3/4'1
* CPY $C0 (Y - M) -> NZC (Immediate) 2/2
* CMP $C1 (A - M) -> NZC (Ind,X) 2/6
NOP $C2 [no operation] (Immediate) 2/2
DCP $C3 M <- (M)-1, (A-M) -> NZC (Ind,X) 2/8
* CPY $C4 (Y - M) -> NZC (Z-Page) 2/3
* CMP $C5 (A - M) -> NZC (Z-Page) 2/3
* DEC $C6 M <- (M) - 1 (Z-Page) 2/5
DCP $C7 M <- (M)-1, (A-M) -> NZC (Z-Page) 2/5
* INY $C8 Y <- (Y) + 1 (Implied) 1/2
* CMP $C9 (A - M) -> NZC (Immediate) 2/2
* DEX $CA X <- (X) - 1 (Implied) 1/2
SBX $CB X <- (X)/\(A) - M (Immediate) 2/2
* CPY $CC (Y - M) -> NZC (Absolute) 3/4
* CMP $CD (A - M) -> NZC (Absolute) 3/4
* DEC $CE M <- (M) - 1 (Absolute) 3/6
DCP $CF M <- (M)-1, (A-M) -> NZC (Absolute) 3/6
* BNE $D0 if Z=0, PC = PC + offset (Relative) 2/2'2
* CMP $D1 (A - M) -> NZC ((Ind),Y) 2/5'1
JAM $D2 [locks up machine] (Implied) 1/-
DCP $D3 M <- (M)-1, (A-M) -> NZC ((Ind),Y) 2/8
NOP $D4 [no operation] (Z-Page,X) 2/4
* CMP $D5 (A - M) -> NZC (Z-Page,X) 2/4
* DEC $D6 M <- (M) - 1 (Z-Page,X) 2/6
DCP $D7 M <- (M)-1, (A-M) -> NZC (Z-Page,X) 2/6
* CLD $D8 D <- 0 (Implied) 1/2
* CMP $D9 (A - M) -> NZC (Absolute,Y) 3/4'1
NOP $DA [no operation] (Implied) 1/2
DCP $DB M <- (M)-1, (A-M) -> NZC (Absolute,Y) 3/7
NOP $DC [no operation] (Absolute,X) 3/4'1
* CMP $DD (A - M) -> NZC (Absolute,X) 3/4'1
* DEC $DE M <- (M) - 1 (Absolute,X) 3/7
DCP $DF M <- (M)-1, (A-M) -> NZC (Absolute,X) 3/7
* CPX $E0 (X - M) -> NZC (Immediate) 2/2
* SBC $E1 A <- (A) - M - ~C (Ind,X) 2/6
NOP $E2 [no operation] (Immediate) 2/2
ISB $E3 M <- (M) - 1,A <- (A)-M-~C (Ind,X) 3/8'1
* CPX $E4 (X - M) -> NZC (Z-Page) 2/3
* SBC $E5 A <- (A) - M - ~C (Z-Page) 2/3
* INC $E6 M <- (M) + 1 (Z-Page) 2/5
ISB $E7 M <- (M) - 1,A <- (A)-M-~C (Z-Page) 2/5
* INX $E8 X <- (X) +1 (Implied) 1/2
* SBC $E9 A <- (A) - M - ~C (Immediate) 2/2
* NOP $EA [no operation] (Implied) 1/2
SBC $EB A <- (A) - M - ~C (Immediate) 1/2
* SBC $ED A <- (A) - M - ~C (Absolute) 3/4
* CPX $EC (X - M) -> NZC (Absolute) 3/4
* INC $EE M <- (M) + 1 (Absolute) 3/6
ISB $EF M <- (M) - 1,A <- (A)-M-~C (Absolute) 3/6
* BEQ $F0 if Z=1, PC = PC + offset (Relative) 2/2'2
* SBC $F1 A <- (A) - M - ~C ((Ind),Y) 2/5'1
JAM $F2 [locks up machine] (Implied) 1/-
ISB $F3 M <- (M) - 1,A <- (A)-M-~C ((Ind),Y) 2/8
NOP $F4 [no operation] (Z-Page,X) 2/4
* SBC $F5 A <- (A) - M - ~C (Z-Page,X) 2/4
* INC $F6 M <- (M) + 1 (Z-Page,X) 2/6
ISB $F7 M <- (M) - 1,A <- (A)-M-~C (Z-Page,X) 2/6
* SED $F8 D <- 1 (Implied) 1/2
* SBC $F9 A <- (A) - M - ~C (Absolute,Y) 3/4'1
NOP $FA [no operation] (Implied) 1/2
ISB $FB M <- (M) - 1,A <- (A)-M-~C (Absolute,Y) 3/7
NOP $FC [no operation] (Absolute,X) 3/4'1
* SBC $FD A <- (A) - M - ~C (Absolute,X) 3/4'1
* INC $FE M <- (M) + 1 (Absolute,X) 3/7
ISB $FF M <- (M) - 1,A <- (A)-M-~C (Absolute,X) 3/7
'1 - Add one if address crosses a page boundry.
'2 - Add 1 if branch succeeds, or 2 if into another page.
'3 - If page boundry crossed then PCH+1 is just PCH
'4 - Sources disputed on exact operation, or sometimes does not work.
'5 - Full eight bit rotation (with carry)
Sources:
Programming the 6502, Rodney Zaks, (c) 1983 Sybex
Paul Ojala, Post to Comp.Sys.Cbm (po87553@cs.tut.fi / albert@cc.tut.fi)
D John Mckenna, Post to Comp.Sys.Cbm (gudjm@uniwa.uwa.oz.au)
Compiled by Craig Taylor (duck@pembvax1.pembroke.edu)
APPENDIX E
----------
; C64 Kernal Jump Table
;
ff81 jmp $ff5b cint Init Editor & Video Chips
ff84 jmp $fd23 ioinit Init I/O Devices, Ports & Timers
ff87 jmp $fd50 ramtas Init Ram & Buffers
ff8a jmp $fd15 restor Restore Vectors
ff8d jmp $fd1a vector Change Vectors For User
ff90 jmp $fe18 setmsg Control OS Messages
ff93 jmp $edb9 secnd Send SA After Listen
ff96 jmp $edc7 tksa Send SA After Talk
ff99 jmp $fe25 memtop Set/Read System RAM Top
ff9c jmp $fe34 membot Set/Read System RAM Bottom
ff9f jmp $ea87 scnkey Scan Keyboard
ffa2 jmp $fe21 settmo Set Timeout In IEEE
ffa5 jmp $ee13 acptr Handshake Serial Byte In
ffa8 jmp $eddd ciout Handshake Serial Byte Out
ffab jmp $edef untalk Command Serial Bus UNTALK
ffae jmp $edfe unlsn Command Serial Bus UNLISTEN
ffb1 jmp $ed0c listn Command Serial Bus LISTEN
ffb4 jmp $ed09 talk Command Serial Bus TALK
ffb7 jmp $fe07 readss Read I/O Status Word
ffba jmp $fe00 setlfs Set Logical File Parameters
ffbd jmp $fdf9 setnam Set Filename
ffc0 jmp ($031a) (iopen) Open Vector [f34a]
ffc3 jmp ($031c) (iclose) Close Vector [f291]
ffc6 jmp ($031e) (ichkin) Set Input [f20e]
ffc9 jmp ($0320) (ichkout) Set Output [f250]
ffcc jmp ($0322) (iclrch) Restore I/O Vector [f333]
ffcf jmp ($0324) (ichrin) Input Vector, chrin [f157]
ffd2 jmp ($0326) (ichrout) Output Vector, chrout [f1ca]
ffd5 jmp $f49e load Load RAM From Device
ffd8 jmp $f5dd save Save RAM To Device
ffdb jmp $f6e4 settim Set Real-Time Clock
ffde jmp $f6dd rdtim Read Real-Time Clock
ffe1 jmp ($0328) (istop) Test-Stop Vector [f6ed]
ffe4 jmp ($032a) (igetin) Get From Keyboad [f13e]
ffe7 jmp ($032c) (iclall) Close All Channels And Files [f32f]
ffea jmp $f69b udtim Increment Real-Time Clock
ffed jmp $e505 screen Return Screen Organization
fff0 jmp $e50a plot Read / Set Cursor X/Y Position
fff3 jmp $e500 iobase Return I/O Base Address
;fff6 Vectors
fff6 [5252] -
fff8 [5942] SYSTEM
;fffa Transfer Vectors
fffa [fe43] NMI
fffc [fce2] RESET
fffe [ff48] IRQ
APPENDIX F
----------
BASIC KEYWORDS
COMMODORE BASIC KEYWORDS
Common Keywords (Tokens 80 - CB)
Tokens 80 to A2 represent action keywords, while codes B4 trough CA
are function keywords. AA - B3 are BASIC operators.
Token Keyword
80 end
81 for
82 next
83 data
84 input#
85 input
86 dim
87 read
88 let
89 goto
8a run
8b if
8c restore
8d gosub
8e return
8f rem
90 stop
91 on
92 wait
93 load
94 save
95 verify
96 def
97 poke
98 print#
99 print
9a cont
9b list
9c clr
9d cmd
9e sys
9f open
a0 close
a1 get
a2 new
------------------
a3 tab(
a4 to
a5 fn
a6 spc(
a7 then
a8 not
a9 step
------------------
aa +
ab -
ac *
ad /
ae ^
af and
b0 or
b1 >
b2 =
b3 <
------------------
b4 sgn
b5 int
b6 abs
b7 usr
b8 fre
b9 pos
ba sqr
bb rnd
bc log
bd exp
be cos
bf sin
c0 tan
c1 atn
c2 peek
c3 len
c4 str$
c5 val
c6 asc
c7 chr$
c8 left$
c9 right$
ca mid$
------------------
cb go
ff pi
Extension Keywords (Tokens CC - FE)
The following codes are defined differently in each Basic version.
The leftmost column shows VIC Super Expander commands (CC trough DD).
Basic 3.5 and 7.0 differ in codes CE and FE, which are prefixes in 7.0,
whereas in 3.5 CE = rlum and FE is unused.
Codes CC to D4 (3.5, 7.0 and 10.0) are function keywords, and D5 trough
FA are action keywords.
Token Keyword
2.0 Super 4.0 3.5/7.0 10.0
cc key concat rgr rgr 2)
cd graphic dopen rclr rclr 2)
ce scnclr dclose rlum/*prefix* *prefix*
cf circle record joy joy
d0 draw header rdot rdot 2)
d1 region collect dec dec
d2 color backup hex$ hex$
d3 point copy err$ err$
d4 sound append instr instr
d5 char dsave else else
d6 paint dload resume resume
d7 rpot catalog trap trap
d8 rpen rename tron tron
d9 rsnd scratch troff troff
da rcolr directory sound sound
db rgr vol vol
dc rjoy auto auto
dd rdot pudef pudef
de graphic graphic
df paint paint 2)
e0 char char
e1 box box
e2 circle circle
e3 gshape paste 2)
e4 sshape cut 2)
e5 draw line
e6 locate locate 2)
e7 color color
e8 scnclr scnclr
e9 scale scale 2)
ea help help
eb do do
ec loop loop
ed exit exit
ee directory dir
ef dsave dsave
f0 dload dload
f1 header header
f2 scratch scratch
f3 collect collect
f4 copy copy
f5 rename rename
f6 backup backup
f7 delete delete
f8 renumber renumber
f9 key key
fa monitor monitor
--------------------------
fb using using
fc until until
fd while while
fe *prefix* *prefix*
Prefixed Extension Keywords (Tokens CE02 - CE0A)
The following codes implement function keywords. Basics 7.0 and 10.0 only.
Token Keyword
ce00
ce01
ce02 pot
ce03 bump
ce04 pen
ce05 rspos
ce06 rsprite
ce07 rspcolor
ce08 xor
ce09 rwindow
ce0a pointer
Prefixed Extension Keywords (Tokens FE02 - FE26)
The following codes are for 7.0 and 10.0 only. Keywords in the
middle are commom.
Token Keyword
7.0 10.0
fe00
fe01
fe02 bank
fe03 filter
fe04 play
fe05 tempo
fe06 movspr
fe07 sprite
fe08 sprcolor
fe09 rreg
fe0a envelope
fe0b sleep
fe0c catalog
fe0d dopen
fe0e append
fe0f dclose
fe10 bsave
fe11 bload
fe12 record
fe13 concat
fe14 dverify
fe15 dclear
fe16 sprsav
fe17 collision
fe18 begin
fe19 bend
fe1a window
fe1b boot
fe1c width 2)
fe1d sprdef 2)
fe1e quit 1) 2)
fe1f stash dma
fe20
fe21 fetch dma
fe22
fe23 swap dma
fe24 off 1) 2)
fe25 fast
fe26 slow
fe27 type
fe28 bverify
fe29 ectory (diRectorY)
fe2a erase
fe2b find
fe2c change
fe2d set 3)
fe2e screen
fe2f polygon
fe30 ellipse
fe31 viewport 2)
fe32 gcopy 2)
fe33 pen
fe34 palette
fe35 dmode
fe36 dpat
fe37 pic 2)
fe38 genlock
fe39 foreground
fe3a
fe3b background
fe3c border
fe3d highlight
Notes:
1) Gives "unimplemented command error" on BASIC 7.0
2) Gives "unimplemented command error" on BASIC 10.0 v0.9
3) Only 'set def' is implemented.
APPENDIX G
---------------
REU'S
The following is based on the Commodore 1764 user's manual (german
version)
Contents:
1) External RAM Access With REUs
2) RAM Expansion Controller (REC) Registers
3) How To Recognize The REU
4) Simple RAM Transfer
5) Additional Features
6) Transfer Speed
7) Interrupts
8) Executing Code In Expanded Memory
9) Other Useful Applications Of The REU
10) Comparision Of Bank Switching and DMA
1) _External RAM Access With REUs_
The REUs provide additional RAM for the C64/128. Three types of REUs
have been produced by Commodore. These are the 1700, 1764 and 1750 with
128, 256 and 512 KBytes built in RAM. However they can be extended up to
several MBytes. The external memory can not be addressed directly by
the C64 with it's 16-bit address space. It has to be transferred from an
to the main memory of the C64. For that purpose there is a built in RAM
Expansion Controller (REC) which transfers memory between the C64 and the
REU using Direct Memory Access (DMA). It can also be used for other
purposes.
---
REU means Ram Expansion Unit. There are several different ones. The
official Commodore REU's are the 1700, 1764 and 1750 which are
respectively 128, 256 and 512Kb of memory (not directly addressable of
course). There seem to be hacks to expand these to 1Mb or even 2Mb. I
myself have recently made 512K in the 256K cartridge without any
difficulties. CLD, an american company makes clones of the 1750 and maybe
others. These clones are smaller than the originals but probably not as
expandable. I have a 1750 Clone (512Kb) and it seems to be 100%
compatible (no, not 99.9% but really 100%).
Furthermore there is the Georam expansion. This cartridge is ugly as hell
and only works with GEOS. I believe it's also 512K. In my opinion, the
real REU is better in every respect. (W. Lamee)
---
2) _RAM Expansion Controller (REC) Registers_
The REC is programmed by accessing it's registers, that appear memory
mapped in the I/O-area between $DF00 and $DF0A when a REU is connected
through the expansion port of the C64. They can be read and written to
like VIC- and SID-registers.
$DF00: STATUS REGISTER
various information can be obtained (read only)
Bit 7: INTERRUPT PENDING (1 = interrupt waiting to be served)
unnecessary
Bit 6: END OF BLOCK (1 = transfer complete)
unnecessary
Bit 5: FAULT (1 = block verify error)
Set if a difference between C64- and REU-memory areas was found
during a compare-command.
Bit 4: SIZE (1 = 256 KB)
Seems to indicate the size of the RAM-chips. It is set on 1764
and 1750 and clear on 1700.
Bits 3..0: VERSION
Contains 0 on my REU.
$DF01: COMMAND REGISTER
By writing to this register RAM transfer or comparision can be
executed.
Bit 7: EXECUTE (1 = transfer per current configuration)
This bit must be set to execute a command.
Bit 6: reserved (normally 0)
Bit 5: LOAD (1 = enable autoload option)
With autoload enabled the address and length registers (see
below) will be unchanged after a command execution.
Otherwise the address registers will be counted up to the
address off the last accessed byte of a DMA + 1,
and the length register will be changed (normally to 1).
Bit 4: FF00
If this bit is set command execution starts immediately
after setting the command register.
Otherwise command execution is delayed until write access to
memory position $FF00
Bits 3..2: reserved (normally 0)
Bits 1..0: TRANSFER TYPE
00 = transfer C64 -> REU
01 = transfer REU -> C64
10 = swap C64 <-> REU
11 = compare C64 - REU
$DF02..$DF03: C64 BASE ADDRESS
A 16-bit C64 - base address in low/high order.
$DF04..$DF06: REU BASE ADDRESS
This is a three byte address consisting of a low and
high byte and an expansion bank number.
Normally only bits 2..0 of the expansion bank are valid
(for a maximum of 512 KByte), the other bits are always
set. This must be different if more than 512 KByte are
installed.
$DF07..$DF08: TRANSFER LENGTH
This is a 16-bit value containing the number of bytes to
transfer or compare.
The value 0 stands for 64 Kbytes.
If the transfer length plus the C64 base address exceeds
64K the C64 address will overflow and cause C64 memory
from 0 on to be accessed.
If the transfer length plus the REU base address exceeds
512K the REU address will overflow and cause REU memory
from 0 on to be accessed.
$DF09: INTERRUPT MASK REGISTER
unnecessary
Bit 7: INTERRUPT ENABLE (1 = interrupt enabled)
Bit 6: END OF BLOCK MASK (1 = interrupt on end)
Bit 5: VERIFY ERROR (1 = interrupt on verify error)
Bits 4..0: unused (normally all set)
$DF0A: ADDRESS CONTROL REGISTER
Controlls the address counting during DMA.
If an address is fixed, not a memory block but always the same
byte addressed by the base address register is used for DMA.
Bit 7: C64 ADDRESS CONTROL (1 = fix C64 address)
Bit 6: REU ADDRESS CONTROL (1 = fix REU address)
Bits 5..0: unused (normally all set)
To access the REU-registers in assembly language it is convenient to
define labels something like this:
status = $DF00
command = $DF01
c64base = $DF02
reubase = $DF04
translen = $DF07
irqmask = $DF09
control = $DF0A
3) _How To Recognize The REU_
Normally the addresses between $DF00 and $DF0A are unused. So normally if
values are stored there they get lost. So if you write e.g. the values
1,2,3,... to $DF02..$DF08 and they don't stay there you can be sure that
no REU is connected. However if the values are there it could be because
another kind of module is connected that also uses these addresses.
Another problem is the recognition of the number of RAM banks (64 KByte
units) installed. The SIZE bit only tells that there are at least 2
(1700) or 4 (1764, 1750) banks installed. By trying to access & verify
bytes in as many RAM banks as possible the real size can be determined.
This can be seen in the source to "Dynamic memory allocation for the 128"
in Commodore Hacking Issue 2. (He) personally prefer(s) to let the user
choose if and which REU banks shall be used.
4) _Simple RAM Transfer_
Very little options of the REU are necessary for the main purposes of
RAM expanding.
Just set the base addresses, transfer length and then the command
register.
The following code transfers one KByte containing the screen
memory ($0400..$07FF) to address 0 in the REU:
lda #0
sta control ; to make sure both addresses are counted up
lda #<$0400
sta c64base
lda #>$0400
sta c64base + 1
lda #0
sta reubase
sta reubase + 1
sta reubase + 2
lda #<$0400
sta translen
lda #>$0400
sta translen + 1
lda #%10010000; c64 -> REU with immediate execution
sta command
To transfer the memory back to the C64 replace "lda #%10010000"
by "lda #%10010001".
I think that this subset of 17xx functions would be enough for a
reasonable RAM expansion. However if full compatibility with 17xx REUs
is desired also the more complicated functions have to be implemented.
5) _Additional Features_
Swapping Memory
With the swap-command memory between 17xx and C64 is exchanged. The
programming is the same as in simple RAM transfer.
Comparing Memory
No RAM is transferred but the number of bytes specified in the
transfer length register is compared. If there are differences the
FAULT-bit of the status register is set. This bit is cleared by reading
the status register which has to be done before comparing to get valid
information.
Using All C64 Memory
C64 memory is accessed by the REU normally in the memory configuration
existing during writing to the command register. However in order to be
able to write to the command register the I/O-area has to be active.
If RAM between $D000 and $DFFF or character ROM shall be used it is
possible to delay the execution of the command by storing a command byte
with bit 4 ("FF00") cleared. The command will then be executed
by writing any value to address $FF00.
Example:
< Set base addresses and transfer length >
lda #%10000000 ; transfer C64 RAM -> REU delayed
sta command
sei
lda $01
and #$30
sta $01 ; switch on 64 KByte RAM
lda $FF00 ; to not change the contents of $FF00
sta $FF00 ; execute DMA
lda $01
ora #$37
sta $01 ; switch on normal configuration
cli
6) _Transfer Speed_
During DMA the CPU is halted and the memory access cycles normally
available for the CPU are now used to access one byte each. So with
screen and sprites switched off in every clock cycle (985248 per second
on PAL machines) a byte is transferred. If screen is on or sprites are
enabled transfer is a bit slower, as the VIC exclusively accesses RAM
sometimes. An exact description of those "missing cycles" can be found
in Commodore Hacking Issue 3.
Comparing memory areas is as fast as transfers. (Comparison is stopped
once the first difference is found.)
Swapping memory is only half as fast, as for every bytes two C64 memory
accesses (read & write) are necessary.
7) _Interrupts_
By setting certain bits in the interrupt mask register IRQs at the end
of a DMA can be selected. However as the CPU is halted during DMA it
will always be finished after the store instruction into the command
register or $FF00. So there is no need to check for an "END OF BLOCK"
(bit 6 of status register) or to enable an interrupt.
8) _Executing Code In Expanded Memory_
Code in external memory has always to be copied into C64 memory to be
executed. This is a disadvantage against bank switching systems. However
bank switching can be simulated by the SWAP command. This is done e.g.
in RAMDOS where only 256 bytes of C64 memory are occupied, the 6 KByte
RAM disk driver is swapped in whenever needed. Probably too much
swapping is the reason for RAMDOS to be not really fast at sequential
file access.
9) _Other Useful Applications Of The REU_
The REC is not only useful for RAM transfer and comparison.
One other application (used in GEOS) is to copy C64 RAM areas
by first transferring it to the REU and then transferring it back into
the desired position in C64 memory. Due to the fast DMA this is about 5
times faster than copying memory with machine language instructions.
Interesting things can be done by fixing base addresses. Large C64
areas can be filled very fast with a single byte value by fixing the REU
base address. Thus it is also possible to find the end of an area
containing equal bytes very fast e.g. for data compression.
Fixing the C64 base address is interesting if an I/O-port is used, as
data can be written out faster than normally possible.
It would be possible to use real bitmap graphics in the upper and lower
screen border by changing the "magic byte" (highest by the VIC addressed
byte) in every clock cycle during the border switched off.
Generally the REC could be used as graphics accelerator e.g. to
copy bitmap areas or to copy data fast into the VIC-addressable
16 KByte area.
10) _Comparision Of Bank Switching and DMA_
When comparing bank switching and DMA for memory expansion I think DMA
is the more comfortable methode to program and also is faster in most
cases. The disadvantage with code execution not possible in external
memory could be minimized by copying only the necessary parts into C64
memory. Executing the code will take much more time than copying it
into C64 memory.
APPENDIX H
-----------
ABOUT THE PROCESSOR CHIP
C= Commodore Semiconductor Group
Microprocessors
Description
The 6500/8500 Series family includes a range of software compatible micropro-
cessors which provide a selection of addressable memory range, interrupt input
options and on-chip oscillators and drivers. All of the microprocessors within
the group are directly bus compatible with the MC6800 series IC's.
The family includes ten microprocessors with on-board clock oscillators and
seven microprocessors driven by external clocks. The on-chip clock versions
are aimed at high performance, low cost applications where single phase crystal
or RC inputs provide the time base. The external clock versions are geared for
multiprocessor system applications where maximum timing control is mandatory.
Features
Single +5 volt supply
N channel, silicon gate, depletion load technology
Tri-state address bus, data bus and R/W controlled by AEC input
Direct memory access capability
"Ready" input (for single cycle execution)
56 Instructions with 13 addressing modes
8 bit parallel processing
Decimal and binary arithmetic
True indexing capability
8 bit Bi-directional Data Bus
Programmable Stack Pointer
Available Microprocessors
Device *Clocks Pins IRQ NMI RDY Port Address AEC Sync Speed (MHz)
6502 O 40 X X X - 64K - X 1,2,3,4
65CE02 O 40 X X X - 64K - X 0 - 10
6503 O 28 X X - - 4K - - 1,2,3,4
6504 O 28 X - - - 8K - - 1,2,3,4
6505 O 28 X - X - 4K - - 1,2,3,4
6506 O 28 X - - - 4K - - 1,2,3,4
6507 O 28 - - X - 8K - - 1,2,3,4
6508 E 40 X - - 8 64K X - 1,2,3
6509 E 40 X X X ** 1 M X X 1,2,3
6510 O,E 40 X X X 6,8 64K X - 1,2,3,4
6512 E 40 X X X - 64K - X 1,2,3,4
6513 E 28 X X - - 4K - - 1,2,3,4
6514 E 28 X - - - 8K - - 1,2,3,4
6515 E 28 X - X - 4K - - 1,2,3,4
8501 O 40 X - X 7 64K X - 1,2,3
8502 O 40 X X X 7 64K X - 1,2,3,4
8503 O 40 X - - 8 64K X - 1,2,3,4
* O - On chip clocks, E - External Clocks
** Four extended address pins expand memory capacity to one megabyte.
Pinout
Pin 6502 6510/8500 8502
1 Vss Phi0 in Phi0 in
2 RDY RDY RDY
3 Phi1 out /IRQ /IRQ
4 /IRQ /NMI /NMI
5 NC AEC AEC
6 /NMI Vcc Vcc
7 Sync A0 A0
8 Vcc A1 A1
9 AB0 A2 A2
10 AB1 A3 A3
11 AB2 A4 A4
12 AB3 A5 A5
13 AB4 A6 A6
14 AB5 A7 A7
15 AB6 A8 A8
16 AB7 A9 A9
17 AB8 A10 A10
18 AB9 A11 A11
19 AB10 A12 A12
20 AB11 A13 A13
21 Vss GND GND
22 AB12 A14 A14
23 AB13 A15 A15
24 AB14 P5 P6
25 AB15 P4 P5
26 D7 P3 P4
27 D6 P2 P3
28 D5 P1 P2
29 D4 P0 P1
30 D3 D7 P0
31 D2 D6 D7
32 D1 D5 D6
33 D0 D4 D5
34 R/W D3 D4
35 NC D2 D3
36 NC D1 D2
37 Phi0 in D0 D1
38 SO R/W D0
39 Phi2 out Phi2 out R/W
40 /RES /RES /RES
APPENDIX I
--------------
DIFFERENCES IN PROCESSORS
-----------------------------
I told you that I'd come back with something like this, so here it is!
This is taken from CHacking..
"Q $03F) Now, for those into 6502 machine language. What instruction was not
available on the first 6502 chips?
A $03F) ROR (ROtate Right) was not available until after June, 1976. However,
all Commodore VICs and C64s should have this instruction. Some people
gave instructions that are found on the 65c02, designed by Western
Design Center, and licensed to many companies. However, the 65c02
itself occurs in two flavors, and neither are used in any stock
Commodore product I know of."
Here's another interesting tidbit (from CHACKING)
It seems that the "6510 internal registers were grafted onto a 6502 core
processor."
64 KERNAL ROM DIFFERENCES
Date: Fri Jun 17 16:38:46 1994
Received: from funet.fi by oulu.fi (4.1/SMI-4.1)
6.2 Commodore 64 KERNAL ROM versions.
Below is information on differences between the Commodore 64
KERNAL revisions R1, R2, R3 and the Commodore SX-64 and the
Commodore 4064 ROMs. The chronological order must be R1, R2, 4064,
R3 and SX-64.
The KERNAL ROM R1 was obviously used only in early NTSC systems.
It lacks the PAL/NTSC detection, and always uses white color while
clearing the screen. The white color feature is from the VIC-20
ROM, but the VIC had a white background by default. Thus, this
feature can be listed as a bug. The CIA 1 timer A will always
divide the system clock through $411C == 16668. The other ROMs use
the values $4026 an $4296, depending on the system version
(PAL/NTSC), so their interrupt frequency is 985248 Hz / 16422 ==
59.996 Hz or 1022727 Hz / 17046 == 59.998 Hz. Note that both
clock divisor values differ from the value used in the KERNAL R1.
The PAL/NTSC flag ($2A6) affects the RS-232 timer settings as well.
It seems that the new RS-232 tables for the PAL have been created on
the upper BASIC interpreter area ($E000--$E4FF), from the address
$E4EC on. Surprisingly also the original NTSC tables have been
changed. Very probably the units running the KERNAL R1 had a slower
clock frequency. Extrapolating from the interrupt timer values,
they ran at 1.0000 MHz. Now this makes sense, since the first
(NTSC) video chips had 262 lines per frame and 64 cycles per line.
The frame rate was thus 1 MHz / 262 / 64 == 59.637 Hz. The newer
NTSC units run at 1022727 Hz and draw 263 lines per frame and use 65
cycles per line. This produces a frame rate of 59.826 Hz. Well,
now it is very obvious that there has been at least one mother board
type that has only been used on NTSC units. Probably the processor
clock was created from a 8 MHz chrystal frequency, which served as
the dot clock. The latter NTSC units generate the processor clock
by dividing the chrystal frequency of 14318181 Hz by 14, and the dot
clock will be generated by octacoupling the processor clock.
The PAL systems have been developed later, and they always run at
the same clock frequency, 17734472 Hz / 18. The frame rate has
always been 17734472 Hz / 312 / 63 == 50.125 Hz on those puppies.
The changes in the latter ROM revisions were mainly cosmetical.
There were some bugs corrected in the R3 revision, though.
Format for list:
Address: 901227-01 (Commodore 64 KERNAL R1, $FF80 content $AA)
901227-02 (Commodore 64 KERNAL R2, $FF80 content $00)
901227-03 (Commodore 64 KERNAL R3, $FF80 content $03)
??????-?? (SX-64 or DX-64 KERNAL, $FF80 content $43)
??????-?? (4064 aka PET 64 aka Educator 64, $FF80 content $64)
E119: C9, FF
AD, E4
AD, E4
AD, E4
AD, E4
E42D: 20, 1E, AB
20, 1E, AB
20, 1E, AB
20, 1E, AB
4C, 41, E4
E477: 20, 20, 2A, 2A, 2A, 2A, 20, 43, 4F, 4D, 4D, 4F, 44, 4F, 52, 45,
20, 20, 2A, 2A, 2A, 2A, 20, 43, 4F, 4D, 4D, 4F, 44, 4F, 52, 45,
20, 20, 2A, 2A, 2A, 2A, 20, 43, 4F, 4D, 4D, 4F, 44, 4F, 52, 45,
20, 20, 20, 2A, 2A, 2A, 2A, 2A, 20, 20, 53, 58, 2D, 36, 34, 20,
2A, 2A, 2A, 2A, 20, 43, 4F, 4D, 4D, 4F, 44, 4F, 52, 45, 20, 34,
-: 20, 36, 34, 20, 42, 41, 53, 49, 43, 20, 56, 32, 20, 2A, 2A, 2A,
20, 36, 34, 20, 42, 41, 53, 49, 43, 20, 56, 32, 20, 2A, 2A, 2A,
20, 36, 34, 20, 42, 41, 53, 49, 43, 20, 56, 32, 20, 2A, 2A, 2A,
42, 41, 53, 49, 43, 20, 56, 32, 2E, 30, 20, 20, 2A, 2A, 2A, 2A,
30, 36, 34, 20, 20, 42, 41, 53, 49, 43, 20, 56, 32, 2E, 30, 20,
-: 2A, 0D, 0D, 20, 36, 34, 4B, 20, 52, 41, 4D, 20, 53, 59, 53, 54,
2A, 0D, 0D, 20, 36, 34, 4B, 20, 52, 41, 4D, 20, 53, 59, 53, 54,
2A, 0D, 0D, 20, 36, 34, 4B, 20, 52, 41, 4D, 20, 53, 59, 53, 54,
2A, 0D, 0D, 20, 36, 34, 4B, 20, 52, 41, 4D, 20, 53, 59, 53, 54,
2A, 2A, 2A, 2A, 0D, 0D, 00, 20, 20, 20, 20, 20, 20, 20, 20, 20,
-: 45, 4D, 20, 20, 00, 2B
45, 4D, 20, 20, 00, 5C
45, 4D, 20, 20, 00, 81
45, 4D, 20, 20, 00, B3
20, 20, 20, 20, 20, 63
E4AD: AA, AA, AA, AA, AA, AA, AA, AA, AA, AA
48, 20, C9, FF, AA, 68, 90, 01, 8A, 60
48, 20, C9, FF, AA, 68, 90, 01, 8A, 60
48, 20, C9, FF, AA, 68, 90, 01, 8A, 60
48, 20, C9, FF, AA, 68, 90, 01, 8A, 60
E4C8: AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA,
AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA,
AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, 85, A9, A9, 01, 85,
AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, 85, A9, A9, 01, 85,
2C, 86, 02, 30, 0A, A9, 00, A2, 0E, 9D, 20, D0, CA, 10, FA, 4C,
-: AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA,
AA, AA, AD, 21, D0, 91, F3, 60, 69, 02, A4, 91, C8, D0, 04, C5,
AB, 60, AD, 86, 02, 91, F3, 60, 69, 02, A4, 91, C8, D0, 04, C5,
AB, 60, AD, 86, 02, 91, F3, 60, 69, 02, A4, 91, C8, D0, 04, C5,
87, EA, AD, 21, D0, 91, F3, 60, 69, 02, A4, 91, C8, D0, 04, C5,
-: AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA,
A1, D0, F7, 60, 19, 26, 44, 19, 1A, 11, E8, 0D, 70, 0C, 06, 06,
A1, D0, F7, 60, 19, 26, 44, 19, 1A, 11, E8, 0D, 70, 0C, 06, 06,
A1, D0, F7, 60, 19, 26, 44, 19, 1A, 11, E8, 0D, 70, 0C, 06, 06,
A1, D0, F7, 60, 19, 26, 44, 19, 1A, 11, E8, 0D, 70, 0C, 06, 06,
-: AA, AA, AA, AA, AA, AA, AA, AA
D1, 02, 37, 01, AE, 00, 69, 00
D1, 02, 37, 01, AE, 00, 69, 00
D1, 02, 37, 01, AE, 00, 69, 00
D1, 02, 37, 01, AE, 00, 69, 00
E535: 0E
0E
0E
06
01
E57C: B5, D9, 29, 03, 0D, 88, 02, 85, D2, BD, F0, EC, 85, D1, A9, 27,
B5, D9, 29, 03, 0D, 88, 02, 85, D2, BD, F0, EC, 85, D1, A9, 27,
20, F0, E9, A9, 27, E8, B4, D9, 30, 06, 18, 69, 28, E8, 10, F6,
20, F0, E9, A9, 27, E8, B4, D9, 30, 06, 18, 69, 28, E8, 10, F6,
20, F0, E9, A9, 27, E8, B4, D9, 30, 06, 18, 69, 28, E8, 10, F6,
-: E8, B4, D9, 30, 06, 18, 69, 28, E8, 10, F6, 85, D5, 60
E8, B4, D9, 30, 06, 18, 69, 28, E8, 10, F6, 85, D5, 60
85, D5, 4C, 24, EA, E4, C9, F0, 03, 4C, ED, E6, 60, EA
85, D5, 4C, 24, EA, E4, C9, F0, 03, 4C, ED, E6, 60, EA
85, D5, 4C, 24, EA, E4, C9, F0, 03, 4C, ED, E6, 60, EA
E5EF: 09
09
09
0F
09
E5F4: E6, EC
E6, EC
E6, EC
D7, F0
E6, EC
E622: ED, E6
ED, E6
91, E5
91, E5
91, E5
EA07: A9, 20, 91, D1, A9, 01, 91, F3, 88, 10, F5, 60
A9, 20, 91, D1, 20, DA, E4, EA, 88, 10, F5, 60
20, DA, E4, A9, 20, 91, D1, 88, 10, F6, 60, EA
20, DA, E4, A9, 20, 91, D1, 88, 10, F6, 60, EA
A9, 20, 91, D1, 20, DA, E4, EA, 88, 10, F5, 60
ECCA: 1B, 00
9B, 37
9B, 37
9B, 37
9B, 37
ECD2: 00
0F
0F
0F
0F
ECD9: 0E, 06, 01, 02, 03, 04, 00, 01, 02, 03, 04, 05, 06, 07
0E, 06, 01, 02, 03, 04, 00, 01, 02, 03, 04, 05, 06, 07
0E, 06, 01, 02, 03, 04, 00, 01, 02, 03, 04, 05, 06, 07
03, 01, 01, 02, 03, 04, 00, 01, 02, 03, 04, 05, 06, 07
00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00
EF94: 85, A9, 60
85, A9, 60
4C, D3, E4
4C, D3, E4
85, A9, 60
F0D8: 0D, 50, 52, 45, 53, 53, 20, 50, 4C, 41, 59, 20, 4F, 4E, 20
0D, 50, 52, 45, 53, 53, 20, 50, 4C ,41, 59, 20, 4F, 4E, 20
0D, 50, 52, 45, 53, 53, 20, 50, 4C ,41, 59, 20, 4F, 4E, 20
4C, 4F, 41, 44, 22, 3A, 2A, 22, 2C, 38, 0D, 52, 55, 4E, 0D
0D, 50, 52, 45, 53, 53, 20, 50, 4C ,41, 59, 20, 4F, 4E, 20
F387: 03
03
03
08
03
F428: D0, 0B, AD, 95, 02, 0A, A8, AD, 96, 02, 4C, 3F, F4, 0A, AA, BD,
F0, 1C, 0A, AA, AD, A6, 02, D0, 09, BC, C1, FE, BD, C0, FE, 4C,
F0, 1C, 0A, AA, AD, A6, 02, D0, 09, BC, C1, FE, BD, C0, FE, 4C,
F0, 1C, 0A, AA, AD, A6, 02, D0, 09, BC, C1, FE, BD, C0, FE, 4C,
F0, 1C, 0A, AA, AD, A6, 02, D0, 09, BC, C1, FE, BD, C0, FE, 4C,
-: C0, FE, 0A, A8, BD, C1, FE, 2A, 48, 98, 69, C8, 8D, 99, 02, 68,
40, F4, BC, EB, E4, BD, EA, E4, 8C, 96, 02, 8D, 95, 02, AD, 95,
40, F4, BC, EB, E4, BD, EA, E4, 8C, 96, 02, 8D, 95, 02, AD, 95,
40, F4, BC, EB, E4, BD, EA, E4, 8C, 96, 02, 8D, 95, 02, AD, 95,
40, F4, BC, EB, E4, BD, EA, E4, 8C, 96, 02, 8D, 95, 02, AD, 95,
-: 69, 00, 8D, 9A, 02
02, 0A, 20, 2E, FF
02, 0A, 20, 2E, FF
02, 0A, 20, 2E, FF
02, 0A, 20, 2E, FF
F459: 4C
20
20
20
20
F4B7: 7B
7B
7B
F7
7B
F5F9: 5F
5F
5F
F7
5F
F762: 91, C9, FF, F0, FA
A1, 20, E0, E4, EA
A1, 20, E0, E4, EA
A1, 20, E0, E4, EA
A1, 20, E0, E4, EA
F81F: 2F
2F
2F
2F
2B
F82C: 2F
2F
2F
2F
2B
FCFC: 18, E5
5B, FF
5B, FF
5B, FF
5B, FF
FDDD: A9, 1B, 8D, 04, DC, A9, 41, 8D, 05, DC, A9, 81, 8D, 0D, DC, AD,
AD, A6, 02, F0, 0A, A9, 25, 8D, 04, DC, A9, 40, 4C, F3, FD, A9,
AD, A6, 02, F0, 0A, A9, 25, 8D, 04, DC, A9, 40, 4C, F3, FD, A9,
AD, A6, 02, F0, 0A, A9, 25, 8D, 04, DC, A9, 40, 4C, F3, FD, A9,
AD, A6, 02, F0, 0A, A9, 25, 8D, 04, DC, A9, 40, 4C, F3, FD, A9,
-: 0E, DC, 29, 80, 09, 11, 8D, 0E, DC, 4C, 8E, EE
95, 8D, 04, DC, A9, 42, 8D, 05, DC, 4C, 6E, FF
95, 8D, 04, DC, A9, 42, 8D, 05, DC, 4C, 6E, FF
95, 8D, 04, DC, A9, 42, 8D, 05, DC, 4C, 6E, FF
95, 8D, 04, DC, A9, 42, 8D, 05, DC, 4C, 6E, FF
FEC2: AC, 26, A7, 19, 5D, 11, 1F, 0E, A1, 0C, 1F, 06, DD, 02, 3D, 01,
C1, 27, 3E, 1A, C5, 11, 74, 0E, ED, 0C, 45, 06, F0, 02, 46, 01,
C1, 27, 3E, 1A, C5, 11, 74, 0E, ED, 0C, 45, 06, F0, 02, 46, 01,
C1, 27, 3E, 1A, C5, 11, 74, 0E, ED, 0C, 45, 06, F0, 02, 46, 01,
C1, 27, 3E, 1A, C5, 11, 74, 0E, ED, 0C, 45, 06, F0, 02, 46, 01,
-: B2, 00, 6C
B8, 00, 71
B8, 00, 71
B8, 00, 71
B8, 00, 71
FF08: 93, 02, 29, 0F, D0, 0C, AD, 95, 02, 8D, 06, DD, AD, 96, 02, 4C,
95, 02, 8D, 06, DD, AD, 96, 02, 8D, 07, DD, A9, 11, 8D, 0F, DD,
95, 02, 8D, 06, DD, AD, 96, 02, 8D, 07, DD, A9, 11, 8D, 0F, DD,
95, 02, 8D, 06, DD, AD, 96, 02, 8D, 07, DD, A9, 11, 8D, 0F, DD,
95, 02, 8D, 06, DD, AD, 96, 02, 8D, 07, DD, A9, 11, 8D, 0F, DD,
-: 25, FF, 0A, AA, BD, C0, FE, 8D, 06, DD, BD, C1, FE, 8D, 07, DD,
A9, 12, 4D, A1, 02, 8D, A1, 02, A9, FF, 8D, 06, DD, 8D, 07, DD,
A9, 12, 4D, A1, 02, 8D, A1, 02, A9, FF, 8D, 06, DD, 8D, 07, DD,
A9, 12, 4D, A1, 02, 8D, A1, 02, A9, FF, 8D, 06, DD, 8D, 07, DD,
A9, 12, 4D, A1, 02, 8D, A1, 02, A9, FF, 8D, 06, DD, 8D, 07, DD,
-: A9, 11, 8D, 0F, DD, A9, 12, 4D, A1, 02, 8D, A1, 02, A9, FF, 8D,
AE, 98, 02, 86, A8, 60, AA, AD, 96, 02, 2A, A8, 8A, 69, C8, 8D,
AE, 98, 02, 86, A8, 60, AA, AD, 96, 02, 2A, A8, 8A, 69, C8, 8D,
AE, 98, 02, 86, A8, 60, AA, AD, 96, 02, 2A, A8, 8A, 69, C8, 8D,
AE, 98, 02, 86, A8, 60, AA, AD, 96, 02, 2A, A8, 8A, 69, C8, 8D,
-: 06, DD, 8D, 07, DD, AE, 98, 02, 86, A8, 60
99, 02, 98, 69, 00, 8D, 9A, 02, 60, EA, EA
99, 02, 98, 69, 00, 8D, 9A, 02, 60, EA, EA
99, 02, 98, 69, 00, 8D, 9A, 02, 60, EA, EA
99, 02, 98, 69, 00, 8D, 9A, 02, 60, EA, EA
FF5B: AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA,
20, 18, E5, AD, 12, D0, D0, FB, AD, 19, D0, 29, 01, 8D, A6, 02,
20, 18, E5, AD, 12, D0, D0, FB, AD, 19, D0, 29, 01, 8D, A6, 02,
20, 18, E5, AD, 12, D0, D0, FB, AD, 19, D0, 29, 01, 8D, A6, 02,
20, 18, E5, AD, 12, D0, D0, FB, AD, 19, D0, 29, 01, 8D, A6, 02,
-: AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA, AA,
4C, DD, FD, A9, 81, 8D, 0D, DC, AD, 0E, DC, 29, 80, 09, 11, 8D,
4C, DD, FD, A9, 81, 8D, 0D, DC, AD, 0E, DC, 29, 80, 09, 11, 8D,
4C, DD, FD, A9, 81, 8D, 0D, DC, AD, 0E, DC, 29, 80, 09, 11, 8D,
4C, DD, FD, A9, 81, 8D, 0D, DC, AD, 0E, DC, 29, 80, 09, 11, 8D,
-: AA, AA, AA, AA, AA
0E, DC, 4C, 8E, EE
0E, DC, 4C, 8E, EE
0E, DC, 4C, 8E, EE
0E, DC, 4C, 8E, EE
FF80: AA
00
03
43
64
FF82: 18, E5
53, FF
53, FF
53, FF
53, FF
FFF8: 42, 59
42, 59
42, 59
42, 59
00, 00
APPENDIX J
----------
CHIP INFORMATION CHART
IC'S
-----
LOCATION IC NUMBER DESCRIPTION
-------- --------- -----------
U1 6526 CIA #1 COMPLEX INTERFACE ADAPTER
U2 6526 CIA #2 "
U3 901226-01 NMOS 8192X8 STATIC BASIC ROM
U4 901227-XX NMOS 8192X8 STATIC KERNAL ROM
U5 901225-01 NMOS 4096X8 STATIC CHARACTER ROM
U6 2114-30L/MCM2114P20 NMOS 1024X8 STATIC RAM
U7 6510 NMOS MPU (CPU)
U8 7406N/M53206P QUAD OPERATIONAL AMPLIFIER
U9 4164-2/MK4564N-20 NMOS 65536X1-BIT DYNAMIC RAM
U10 4164-2/MK4564N-20 NMOS 65536X1-BIT DYNAMIC RAM
U11 4164-2/MK4564N-20 NMOS 65536X1-BIT DYNAMIC RAM
U12 4164-2/MK4564N-20 NMOS 65536X1-BIT DYNAMIC RAM
U13 74LS257 QUAD 2-INPUT TRI-STATE MULTIPLEXER
U14 74LS258 TTL DIGITAL MULTIPLEXER
U15 74LS139 DUAL 2/4 DECODER DEMULTIPLEXER
U16 4066 CMOS QUAD ANALOG SWITCH
U17 82S100 FIELD PROGRAMMABLE PLA
U18 6581 SID SOUND INTERFACE DEVICE
U19 6567 VIC VIDEO INTERFACE CHIP
U20 556/MC3456 DUAL 555 TIMER
U21 4164-2 RAM NMOS 65536X1-BIT DYNAMIC RAM
U22 4164-2 RAM NMOS 65536X1-BIT DYNAMIC RAM
U23 4164-2 RAM NMOS 65536X1-BIT DYNAMIC RAM
U24 4164-2 RAM NMOS 65536X1-BIT DYNAMIC RAM
U25 74LS257 QUAD 2-INPUT TRI-STATE MULTIPLEXER
U26 74LS373 8-BIT TRANSPARENT LATCH
U27 75LS08 QUAD 2-INPUT AND
U28 4066 CMOS ANALOG SWITCH
U29 74LS74 QUAD D FLIP-FLOP
U30 74LS193 BINARY UP/DOWN COUNTER
U31 74LS629N DUAL VOLTAGE CONTROLLER OSCILLATOR
U32 MC4044 TTL PHASE FREQUENCY DETECTOR
OTHER COMPONENTS:
LOCATION DEVICE DESCRIPTION
-------- ------ -----------
CR1 1N4371 2.7-VOLT ZENER DIODE
CR2 1N755 7.5-VOLT ZENER DIODE
CR3 1N914 SIGNAL DIODE
CR4 VM08 (P/S) BRIDGE RECTIFIER DIODE
CR5 1N4001 (P/S) POWER DIODE
CR6 1N4001 (P/S) POWER DIODE
Q1 2N4401 TRANSISTOR
Q2 2N3904 "
Q3 TP29B "
Q4 PN2222 "
Q5 PN2222 "
Q6 PN2222 "
Q7 PN2222A "
Q8 PN2222 "
VR1 MD7812CT/UA7812UC FIXED POSITIVE LINEAR VOLTAGE REG.
VR2 MC7805CT " WITH 1500 mA OUTPUT
APPENDIX K
----------
SPECIFICATIONS OF THE COMMODORE 64
MANUFACTURER: COMMODORE BUSINESS SYSTEMS
1200 WILSON DRIVE
WEST CHESTER, PA 19380
SIZE: 2.75"X15.9"X8.0"
WEIGHT: 4.1 LBS.
POWER REQUIRED: LESS THAN 20 WATTS 8.5 WATTS AT 5.V DC
MPU: COMMODORE 6510 MPU
DATA WORD SIZE: 8-BITS
CPU CLOCK SPEED: 1.023 MHz
MEMORY SIZE: 64K
MASS STORAGE CAPABILITY:
UP TO 4 VIC-1541 DISK DRIVES
DATA CASSETTE RECORDER
KEYBOARD SIZE: 65 KEYS
157 CHARACTER CODES
TEXT DISPLAY: 40 UPPERCASE CHARACTERS (2-CHAR SETS)
24 LINES
GRAPHICS CAPABILITY: LOW RES - 160 X 200 PIXELS
HIGH RES - 320 X 200 PIXELS
USER DEFINED SPRITE GRAPHICS
COLOR CAPABILITY: 16 COLORS
INPUT/OUTPUT: CASSETTE I/O
2-CONTROL PORTS FOR GAME PADDLES
CARTRIDGE EXPANSION SLOT
24-PIN USER I/O PORT
6-PIN SERIAL I/O CONNECTION
RF MODULATOR OUTPUT FOR TV DISPLAY
NTSC COMPOSITE COLOR OUTPUT FOR MONITOR
BIBLIOGRAPHY:
------------
1. "Beyond Games: Systems Software for Your 6502 Personal Computer" by Ken
Skier 1981. This book was intended for the C= PET 2001 Computer.
2. "Machine Language for Beginners" by Richard Mansfield, 1983. This book
was intended for the Atari, VIC, Apple, Commodore 64, and PET/CBM
computers.
3. "Assembly Language Programming with the Commodore 64" by Marvin L. De
Jong, 1984.
4. "Commodore 64 Troubleshooting & Repair Guide" by Robert C. Brenner, 1985.
5. "The Commodore 64 Programmer's Reference Guide" by CBM, 19xx.
6. "The Commodore 64 User's Guide" by CBM, 19xx.
7. "CHACKING MAG" (C) 1992 by Craig Taylor
8. "The PC Assembler Tutor" (C) 1989 by Chuck Nelson.
(
geocities.com/timessquare/arcade/Arcade/2045/docs) (
geocities.com/timessquare/arcade/Arcade/2045) (
geocities.com/timessquare/arcade/Arcade) (
geocities.com/timessquare/arcade) (
geocities.com/timessquare)