I think i have used only latest SMART phones. before all these SMART phones comes into market, there was phones, (e.g. Nokia N73) which can wake up @ set alarm time even if its switched off.
I think you have used only latest SMART phones. before all these SMART phones comes into market, there was phones, (e.g. Nokia N73) which can wake up @ set alarm time even if its switched off.
But todays smartphones run Android and its a Linux based operating system. The OS needs to be fully active (and kernel running) to do jobs. So the phone must be on when you set an alarm.
No you guys are wrong. Those older phones had RTCs and they were wired up to allow this.
Linux supports RTCs and wake on RTC.
The question are "Does phone X have and RTC? Are it's GPIOs hooked up to "push" the power button? Do we have a driver? Can we write to it from the OS?"