ATmega169A/PA/329A/PA/3290A/PA/649A/P/6490A/P

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


ATmega169A/PA
Rev. I	Rev. J	Rev. K
X	X	X
ATmega329A/PA/3290A/PA
Rev. D
X
ATmega649A/P/6490A/P
Rev. B
X

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