Eric_t d

HCS12XDT512 & PLL stability

Discussion created by Eric_t d on Mar 9, 2018
Latest reply on Mar 13, 2018 by Diana Batrlova


I am using HCS12XDT512 with 16MHz crystal and PLL filter. The desired frequency for cpu bus is 14.7MHz.

I have used processor expert to calculate the correct values for SYNR & REFDV.

Processor expert gives SYNR=0x2E and REFDV=0x32.

I have used the S12X PLL filter calculator Beta 2 to check PLL stability.

The problem is that S12X PLL filter calculator, shows that maximum REFDV value is 15 (S12X PLL filter calculator says that the processor expert calculated value is wrong)


I suppose that the processor expert gives correct results and the problem is at S12X PLL filter calculator.

Does anyone know if there is a newer version of S12X PLL filter calculator?


I have attached a picture.