Robin2:
What processor are you using to try the sleep code? Is the library suitable for that processor?...R
It's at ATTiny45, and I have now got it to sleep by removing the brown out code. The problem now is that it always counts 1, which I guess is something to do with sleep and millis().
I have attached the latest code.
Regards,
Les
BeepCounter.ino (8 KB)