2.2.1 Interrupts May Be Lost When Writing the Timer Registers in the Asynchronous Timer
The interrupt will be lost if writing a timer register that is a synchronous timer clock
when the asynchronous Timer/Counter register (TCNTx) is 0x00.
Work Around
Always check that the asynchronous Timer/Counter register neither has the value
0xFF nor 0x00 before writing to the asynchronous
Timer Control Register (TCCRx), asynchronous Timer Counter Register (TCNTx), or
asynchronous Output Compare Register (OCRx).
Affected Silicon Revisions
| ATmega165A/PA | ||
|---|---|---|
| Rev. I | Rev. J | Rev. K |
| X | X | X |
| ATmega325A/PA/3250A/PA | ||
| Rev. D | ||
| X | ||
| ATmega645A/P/6450A/P | ||
| Rev. B | ||
| X | ||