Rainbow Electronics ATmega3290P_V - Manual (Page 366)

366
ATmega329/3290/649/6490
2552H–AVR–11/06
ATmega649 rev. A
• Interrupts may be lost when writing the timer registers in the asynchronous timer
1. Interrupts may be lost when writing the timer registers in the asynchronous
timer
If one of the timer registers which is synchronized to the asynchronous timer2 clock
is written in the cycle before a overflow interrupt occurs, the interrupt may be lost.
Problem Fix/Wortkaround
Always check that the Timer2 Timer/Counter register, TCNT2, does not have the
value 0xFF before writing the Timer2 Control Register, TCCR2, or Output Compare
Register, OCR2.
ATmega6490 rev. A
• Interrupts may be lost when writing the timer registers in the asynchronous timer
1. Interrupts may be lost when writing the timer registers in the asynchronous
timer
If one of the timer registers which is synchronized to the asynchronous timer2 clock
is written in the cycle before a overflow interrupt occurs, the interrupt may be lost.
Problem Fix/Wortkaround
Always check that the Timer2 Timer/Counter register, TCNT2, does not have the
value 0xFF before writing the Timer2 Control Register, TCCR2, or Output Compare
Register, OCR2.