Chung Shien Chai

MC13213 SRB System Clock Configuration

Discussion created by Chung Shien Chai on Feb 9, 2007
Latest reply on Feb 12, 2007 by Chung Shien Chai
I want to use CLKO from Modem as my clocking source to MCU for MC13213. And the frequency i need to set is 16MHz.

What i did is
a. write to modem register 0x0A with value 0x7E80 (to set the CLKO to highest frequency)
b. write to modem register 0x09 with value 0xF3EF (to enable clko_en)
c. write MCU register ICGC1 with value 0x50 (to enable external reference and choose FLL bypass and external reference mode)
d. then i wait until ERCS (bit1) on MCU register ICGS1 to be set

that we what i configure, other register i like ICGC2, i just leave it as default value after reset!

is the configuration i made correct? with that, will MCU get a 16MHz Source Clock from modem on my SRB board?

is it that, with 16MHz source clock, i will get 8M of bus frequency?

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