LPC1764 periodic wakeup

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by samc on Thu Sep 02 10:34:27 MST 2010

I am trying to put my 1764 to deep sleep and wake it every 120ms for a few ms.

My first approach was to use the watchdog timer, but it seems that doesnt work:
The wdt interrupt can only be used once, as the interrupt flag cannot be reset.
So it works for the first 120ms, then the on the next cycle the interrupt is already set, so the isr keeps beeing called infinitely.

Second approach was to use the method described for the LPC11xx in one of the threads here, using a timer match and a GPIO wakeup interrupt. This works for sleep, but also nto for deep sleep, seems the timer is not running in deep sleep.

Does anybody have suggestions on how to do the periodic wakeup?