[Tinyos-host-mote-wg] [Tinyos-2.0wg] proposed mica timer changes

[David Gay]

Based on my many days of fighting T2 on mica2 weirdnesses+performance
issues, I'd like to propose the following changes to the T2 atmega128
subsystem:

- HplTimer0C becomes HplTimer0AsyncC and has weird hacks to defeat
ATmega128 weirdnesses. You'll all be happy to know this requires one
byte of state ;-) In a semi-ideal world, they'd also be an HplTimer0C
for those using timer 0 in non-async (i.e., not the external 32kHz
crystal) mode, but I doubt there's much need for it.

- Atm128Capture/Alarm/CounterP become Atm128Capture/Alarm/CounterC -
these aren't private components.

- AlarmCounter32khzC and AlarmCounterMilliC are two ways of using the
atmel's 8-bit timer 0 w/ 32kHz crystal. You can't use both (not
enforced). They provide the Alarm, Counter and Localtime interfaces in
32-bit forms, at 32kHz or 1kHz.

- TimerMilliC is the standard 1kHz timer, built on AlarmCounterMilliC (for now)

- Timer32khzC is temporarily gone - it didn't work as it was trying to
use the same alarm as TimerMilliC. Ultimately, if we want this, we'll
have to do some sharing of the alarm with TimerMilliC as there's only
one compare register (the best solution would seem to be a hacked
version of VirtualiseTimerC which can virtualise to two different
rates - I'll look into this after pldi).

All this requires a TransformAlarmCounterC component to be added to lib/timer.

David

_______________________________________________
Tinyos-2.0wg mailing list
Tinyos-2.0wg at Mail.Millennium.Berkeley.EDU
https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-2.0wg