The A3000 came with 1MB chip (1), with a optinal extra 1MB (2). The Chip Memory is of DRAM type, 20-pin DIP. Speed = 120ns or less Maximum 2 Meg, organized 256Kb by 4 bits.
Stores the blitter, witch is used to move memory around as fast as possible Are also in charge of accessing the other custom chips Alice is the new version of the chip used in A1200 and A4000
Does the floating point calculations.
Is in charge of Zorro I/II/III expansion ports
Gary, the Gate Array, is used in conjuction with all of the Amiga's peripherals and interfaces, such as the keyboard, floppy drive, and IDE controller. Gary and Gayle both support DMA, or Diretc Memory Access, which allows them to access peripherals while bypassing the CPU. This makes memory access much faster, and is not found on many other computers. In the newer Amigas, Gayle is also responsible for PCMCIA access.
In the Amiga 3000 the brain is Motorola 68030. This have a MMU (Memory Management Unit) and can thereby handle Viritual Memory ie VMM or such programs.
Ramsey controls access to RAM, or so it would seem.
The fast memory is of DRAM type 80ns or less 256Kb by 4 bits or 1Mb by 4 bits in total
8 banks.
There are two types of ZIP memory for the Amiga 3000. Static Column and Page Mode, where
the first type is faster. Amiga 3000 fast memory can handle as high datatransfers as 30
Mb/sec
Not bad for a computor built 1990.
The Amiga manuals say you should not mix the two types, but I have both types in my A3000
and this works.
You have to put the Page Mode in bank 1, but thats it. All memory are in this case handled
as Page Mode.
In early A3000 there were 1Meg DIP Fast and 1Meg DIP chip mem. When upgrading the Fast the DIP version of Fast could be moved to the empty sockets in the Chip RAM section (2), thus giving 2Meg Chip mem.
200 pin expantion slot. Usable for cpu cache or a 68030-68060 cpu. Soon: 68060 50Mhz plus PPC604 200Mhz. (wow)
The Paula chip controls audio output. The audio is in the form of stereo sound using 4 voices, sampled or synthesized. The digital audio is converted into analog audio for output to the speakers, unamplified. This chip is standard on all Amigas.
The Denise and Lisa chips interact with the video display to produce the required screenmodes, whether interlaced or non-interlaced, and to determine the number of bitplanes used in the video display. These are the graphics chips, the Denise being found in OCS and ECS machines, with the Lisa replacing it in AGA machines. They also contain the Copper, which is used to display graphics effects found often in Eurodemos. Last of all, the sprite control hardware is located here.
This chip control the video deinterlacing displays. Have a 12BIT non-programmable buffer. Doubling the standard PAL/NTCS to 31.5kHz making a VGA style monitor usable.
100 pin slot for backplane. ie. ISA, video and zorro slots.
DMA controller. (Direct Memory Access). With this many of the tasks by the custom chips, SCSI and 8520 chips can be done without the cpu. The cpu can do other things.
Well you may bust one of these by unplugging mouse, keyboard or joystick when powered up. You figur out what they do :) OK peripheral controller.
The SCSI chip controls the devices on the SCSI chain. data flows to and from them.
512Kb of the OS is in these. Two types of A3000, the old one with ROM tower and the newer one in picture.
A chip labelled as Fat has a physical shape that allows more pins to access the actual chip from the motherboard than the older rectangular chips. A Fat, Fatter or Super chip also signifies that it is an ECS upgrade to an existing OCS chip. The Fat Agnus is the NTSC/PAL capable upgrade to the original Agnus, which was either NTSC or PAL but not both. The Fatter Agnus has 1024k of Chip RAM in addition, while the Fat Agnus and the original Agnus have only 512k. Last, the Super Agnus contains 2048k of Chip RAM. Super Denise offers some new screen modes over the original Denise chip, but unfortunately it does not increase the number or bitplanes displayable by any of the screenmodes.
The Copper is a true graphics coprocessor located within the Agnus chip. With over 30 special graphics functions, this is best known for its "copper lists", allowing a rainbow of colors to be displayed on any screen mode.
Thank's to Kjell Mesch For making of this page
Take A Look at his pages..