Last night I did some brain storming asto what the I/O requirements will be. During this requirements phase I came across a bit of a delima with the PWM requirements for the motor controller. The motor controller requires two outputs per motor, so this rules out using the onboard PWMout command of the PICAXE, as there are only two dedicated PWM pins on the chip that I’m using. Although I could do it with some additional glue logic in hardware, I don’t really want to do that (as I’m lazy), so now I will be doing it all within the software, this should free up the servo command within the PICAXE, so I can now use this to drive the servo for the sonar unit.
I’m going to be using the PICAXE 28X. With my I/O current configuration of the 22 available I/O on chip, I have 2 Inputs/Outputs and 4 Analogue Inputs Available for future expansion (or and additional 4 inputs if I don’t want to use the analogue inputs). It will be interesting to see if the processor will be fast enough process everything in a timely manner, especially with the motor control and encoders. Well I guess I’m about to find out.
I’m now going to actually get my hands dirty with the PICAXE as I still haven’t plugged the development board into my PC yet 🙂