Цитата(Waso @ Jun 23 2008, 14:14)

Дописал в инициализацию
AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_SYS);
Все ок.
Хм.
SAM7S, SAM7SE:
Цитата
Note: 1. Setting SYSIRQ and ADC bits in the clock set/clear registers of the PMC has no effect. The System Controller is continuously clocked. The ADC clock is automatically started for the first conversion. In Sleep Mode the ADC clock is automatically stopped after each conversion.
SAM7X:
Цитата
Note: 1. Setting SYSC and ADC bits in the clock set/clear registers of the PMC has no effect. The System Controller and ADC are continuously clocked.
В описании PMC_PCER бит (1 << AT91C_ID_SYS) также отсутствует. Значит дело было в чем-то другом. Ищите. "Призовая игра!"