brclr CRGFLG,LOCK,*+0 ;while (!(crg.crgflg.bit.lock==1))
bset CLKSEL,PLLSEL ;engage PLL to system
Reply by Michael Burgess●April 7, 20062006-04-07
I am using a DEMO9S12XDT512 Eval Board. This board is equipped with a
4.000MHz. crystal. I'm trying
to reconfigure the processor to use the internal PLL and bump up the
frequency. After configuring the appropriate
registers, and loading the program, the processor still runs at the
4.000MHz rate. However, if I single step
the writing of the SYNR register, then it runs at my desired frequency.
I try checking and waiting on the LOCK status
bit, but this does not help.
What is the procedure for changing the PLL frequency?