On Saturday 03 June 2006 07:51, Dmitry K. wrote: > Hi. > > For me it has appeared a surprise that it is impossible > to avoid start ADC at transition in a idle state (needed > to reduce power consumption). MCU is ATmega168 (and 48). > It was tryed: > 1. Disable ADC interrapt enable: ADIE==0 > 2. No clear ADC ready: ADIE==0, ADIF==1 > 3. (!) Auto Trigger Mode: ADATE==1 (with timer source) > ==> No results: ADC starts with each 'sleep' instruction.
The datasheet says it quite clearly: "If the ADC is enabled, a conversion starts automatically when this mode is entered." This doesn't depend on auto trigger source or the ADC interrupt settings. The solution is to simply switch the ADC off (ADEN=0). > Certainly, the disabling of interruption (ADIE=0) limits > quantity of starts, but it is no matter, when external > interruptions act in the casual manner. To stop ADC it is > impossible: it is switched off internal AREF. > The most insulting, that in Auto Trigger mode it is > impossible to obtain a regular period. Well, you can use a timer as auto trigger source. > I attach a small test of this. Where? _______________________________________________ AVR-chat mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/avr-chat
