lpcware

WDTOSC for SYS PLL Clock Source

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by ktownsend on Sun Jul 25 23:27:57 MST 2010
In the latest UM for the LPC1343, WDTOSC was removed an an input clock source for PLL.   (P.22 of http://ics.nxp.com/support/documents/microcontrollers/pdf/user.manual.lpc13xx.pdf)

It's still listed in the main clock src select regsiter (MAINCLKSEL), which is helpful since I'm using this feature for controlled SW wakeup from deep sleep even though it's not terribly accurate (+/-40%).

Was the accuracy the main reason it was removed from SYSPLLCLKSEL?  I'm just curious if there are any implications I should keep in mind using WDTOSC as a clock source for the system in deep sleep, as seen in the code below (see [B]pmuWDTClockInit[/B] and [B]pmuDeepSleep[/B][COLOR=#666600]([/COLOR]uint32_t sleepCtrl[COLOR=#666600],[/COLOR] uint32_t wakeupSeconds)):

http://code.google.com/p/lpc1343codebase/source/browse/trunk/core/pmu/pmu.c

Kevin

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