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CPU Sleep mode

Posted: 03 August 2007, 8:03 AM
by bdellabe
I have a ZX-24a microcontroller that I want to have sleep with as little power usage as possible while maintaining its Real Time Clock. I want it to wake up every ten minutes, perform its tasks which require the current time, then go back to sleep. Is there any way I can use the CPUSleep() function, have it wake up after a set amount of time and still have the RTC registers of the microcontroller maintain the correct time?

Thanks

Posted: 03 August 2007, 8:18 AM
by dkinzer
The ZBasic RTC is implemented in software, i.e. it is maintained by responding to a timer interrupt that occurs at a 1024KHz rate. Using a sleep mode that does not allow the CPU to wake up in response to timer interrupts will result in the RTC not being updated correctly.

If you need long sleep times and an accurate RTC, you'll have to use an external RTC.