Haven't done much robot stuff this week, as I have family visting from overseas.
By not using a basic stamp, PIC or AVR, (I'm using a Renesas M16C) I realise that I'm actually making more work for myself as there isn't such a body of knowledge that can simply be plagarised from. For example, I'm trying to do this SRF04 interface for the M16C based on a single timer and a 5-state FSM. Basically, it should go:
state: next state: transition: INIT READY 10ms timer IRQ READY TRIGGER srf_trigger() function call TRIGGER TX 10us timer IRQ TX MEASURE pulsewidth measure on falling edge on input or timer over/ underflow MEASURE READY 10ms timer IRQ
This is based on the expected behaviour shown at the srf04 main page. I'm finding it a bit difficult to get the thing to behave as expected.
Don't get me wrong though, I'm using the M16C starter kit plus (SKP) (it costs about $50 from memory and comes with a C compiler) and I really like it. The SKP board is fairly small (measures about 10x6 cm), has a 2x16 LCD, 3 buttons, 3 leds, and heaps of I/O (you attach the headers), and comes with a USB based programmer/debugger. The uC has 11 timers, 2 or 3 uarts, 3 or 4 INT pins, heaps of ADC. So it does have quite a bit going for it (not to mention about 16 or 32K RAM and a couple of hundred K flash. You can see the one I'm using here.
Cheers, Marcin. (marcincoles__at__yahoo.com)