Hi, I am trying to use an ATtiny85 to transmit time data with an IR LED, but only every 10 seconds, which is more than the maximum time for the watchdog timer you can configure with the watchdog timer prescaler bits. The ATtiny also needs to be in ADC Noise Reduction mode to keep the internal clock…

[image] sbibat2: which is more than the maximum time for the watchdog timer Use the watchdog with 1 second wakeups, and transmit every 10th wakeup. Timing is approximate. Is it possible the watchdog timer is interfering with the clock the millis() function uses? millis() does not run at a…

I guess that could work, thanks for the idea. So even though the sleep mode is ADC Noise Reduction, that's still considered deep sleep and millis() still doesn't work even though the internal clock is still running?

[image] What I read in the datasheet is that also during ADC noise reduction all clocks except the ADC clock are halted. So I suspect millis also stops then.

millis() requires the CPU clock to be running.

[image] sbibat2: I took the watchdog timer code from an example online, [image] Interrupt, sleep ATtIny85, lot of questions Programming Long ago, I wrote "Hot Yet" a t85 /thermistor project for the lavatory; the idea being that a green LED would indicate a water tem…

Ahhh, I was confusing the CPU clock with the oscillator and misunderstood "Main Clock Source Enabled". Thank you all very much for your responses, this is very helpful. And thank you mrburnette for that post, I hadn't come across that when I was looking around. I'm still a little confused as to wh…

ATtiny85 Watchdog Timer with Millis Calculation

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mrburnette April 9, 2022, 2:38pm 6

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ATtiny85 Watchdog Timer with Millis Calculation

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