Before reading this page, I hope you have already read the Triki Board Overview.
Block Diagram of TrikiBoard-1
In the block diagram of TrikiBoard-1 above:
How to Make it
To get the PCB made:
The process to get the PCB made has 2 steps:
Step 1: Getting the Film Made:
Step 2: Getting the PCB Made:
How to Use TrikiBoard
As mentioned earlier, TrikiBoard Version 1.0 is very simple board just to give a head start to Yantriki Level 3 participants who need a Microcontroller Board to control their robots, and it forms a base for EDL Beginners if all they need is a Serial Link to PC or Memory interface to mcu to check their initial project designs.
Power Supply: Apply 8 to 12 volts through the connecter K1. This Battery voltage shall be used to drive the motors by the board. The 7805 chip on-board shall produce 5 volts for the microcontroller. If the 7805 or L298D gets heated too much on your board, add a Heatsink to these chips. Commonly available 7805 would require a heatsink.
Program the microcontroller with the basic test programs given at the end of this page. Then write your own code.
Provisions on TrikiBoard ver. 1.0
Dual H-Bridge for DC Motors
The board can drive 2 DC Motors (which maybe wheel-drive motors). The chip L298D is Dual H-Bridge chip. The motor directions are controlled by the 4 port pins as follows
Speeds of the Motors can be controlled by generating a PWM on these Port pins by software. In other mechatronic applications, a Bi-polar stepper motor (usually 4-wire type) can also be controlled if its 2 windings are connected to K1 & K2 instead of 2 dc-motors.
The 2 LEDs associated with each Motor, on-board, can be used for debugging. Red Led would signify one motor direction and Green the opposite. The L298 can drive practically 12V, 1A consuming motors by each driver.
NOTE: The actual Voltage supplied to the DC motor would be = Vbatt - Vdrop_in_L298D_IC
The usual drop on the transistors inside the L298D is 1.5 to 2.5 Volts. Hence if your battery Voltage is 12V, assume that the motors would practically run at about 10V.
Modification for Running 2 Stepper Motors
If you need to run 2 Stepper Motors, you can add a ULN2908 IC as connected in TrikiBoard-2 and connect 2 Stepper Motors as shown here.
This external RAM is provided in-case your Maze-solving algorithm in Yantriki level 3 requires lot of RAM. EDP users sometimes need just a microcontroller with external RAM to test their initial designs. This board can be used instead of messing with the breadboard wires. The RAM start address is 0000H. :)
A serial link can be established between a PC and TrikiBoard by EDL junta if needed, and Yantriki users for debugging (Note: in actual Yantriki Contest (maze solving) no off-board link/processing is allowed).
If needed, connector K4 has to be connected to the the 9-pin Serial connector of the PC as follows.
Hyperterminal in windows can be used to check the serial link. Use the simple serial test program given in samples to check the serial link.
14 Digital IO Lines and prototyping Area
The 14 digital lines are available on pin headers JP1 and JP3. The general purpose pcb area can be used to add simple sensor amplifier circuits etc. Yantriki users may observe that an ADC is missing in this design. If you need an ADC you can add AD0801 on the prototyping area or use TrikiBoard-2 ! This chip is single channel ADC but is not as wide at AD0809 (with 8 analog channels) so it can fit in the prototype area. Anyway, for current Yantriki level-3 problem, I don't think an ADC is necessary, and simple op-amp based comparators may do the job (big hint!).
The power supplies for the extra circuits/sensors can be taken from pin-header JP2.
Atmel AT89C52 is used in TirikiBoard Ver.1.0, because is it low cost and commonly available in India. For the un-informed, its just an 8052 with 8KB Flash program memory (plus a clock-out option which a beginner will not use).
To write and simulate programs you can download the C51 tools from www.keil.com. The hex files generated after compiling the code, are to be burned in the microcontroller using a programmer. (For IITians in the EE Dept. WEL Lab) The code can be written in C or ASM. Or you can use google to find plenty cross assemblers for 8051.
Sample & Test Code
Sensor Links (Yantriki Level 3 specific)
Sensors associated circuits are deliberately not provided with TrikiBoard, because there can be too many sensing styles, strategies, and circuits, there is lot of scope of innovation here.
The reason TrikiBoard was designed, is that many needed a microcontroller board to run their algorithms on, and were trying to find ways to mount the the usual 8051 Kit on the robot.
Here are some links which could be useful, but I guess you can do a better google search and spend more time searching circuits (or making your own).
(for email address: replace <|a-t|> by @ above and _ by . )