recommendation on task prioritization

[stevech]

Don - yeah, I know- a chip would be better. But (a) I'm lazy and (b) there's no more room on the board.

I don't need to sample both signals simultaneously.

I tried out CountTransitions() for a 6 mSec inteval (instead of WaitForInterrupt). Worked fine. But it doesn't do the longer averaging. I hate to sample much longer - as it impacts interrupt latency in the VM as I understand. The signals I'm sampling are low duty cycle - pulse low for like 5%.

[spamiam]

I was going to suggest considering some extra logic, but I then figured he wanted to minimize the extra hardware. Personally, I would have used extra stuff because it seems "better". But "best" is what works and does it in the simplest way....

Of course I am one for added complexity, just for the fun of it.

-Tony

[spamiam]

[stevech]

regarding use of CountTransitions() for a 6 mSec inteval (instead of WaitForInterrupt)...

The ZBasic documentation says that during the CountTransitions() measurement interval, interrupts are disabled and task switching is blocked, but the RTC ticks accumulate none the less. I wonder if this means that all interrupts except timer ticks are blocked? Or some scheme is used to keep counting in a timer chip on the AVR, then after the measurement interval, read the tallied count and update the time of day. I suppose that ALL interrupts have to be disabled for the sake of measurement accuracy.

Using things that disrupt interrupts is something I tend to avoid - as in the future, some new feature might be infeasbile - such as use of a software UART. These are tradeoffs.

re using timer 2 as a count accumulator: I noted that TOSC on the ZX24 is connected to a port bit by the module's wiriing.

[dkinzer]

[spamiam]

[dkinzer]