Re: TI-H: Radio Link


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Re: TI-H: Radio Link




Actually, the TI protocol is asynchronous... in theory. However
since all programs are fundamentally functions over time (I.E.
one thing per cycle, repeating as time progresses) nothing
is truly asynchronous, including the TI protocol. The AVR
was so fast that it was waiting for a response from the calculator
before the calculator had time to recognize the AVR's response,
and thus was bypassing critical loops in the TI byte send/receive
routines. Even at 1 MHz I've had to add several nops
just to give the calculator time to change its I/O state.

I'm betting Microchip lied a bit about those 200ns numbers,
as the AVR seems to be at least a dozen times faster than the
PIC. I suppose it depends on a lot of things though.

Bryan

Grant Stockly wrote:
> 
> >You reversed the per-cycle times for the AVR and PIC, by the way.
> >The PIC is about 200ns, the AVR is around 62.5. Time = 1 / Frequency.
> 
> I know...  at 10MHz you get 200ns...  at 16MHz you get 62.5...  Your doc
> said you were using a 10MHz crystal and so your routines were
> misconfigured...


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