To reduce external component, we are not using external components for system clock generation. So I use FEI mode and followed the example #3 on manual p.114 to generate 5.4 MHz bus clock with value of ICGC1 = $28 and ICGC2 = $31. Then I use this bus clock to drive TPM1 timer which I program the bits CLKSB:CLKSA equals to 0:1 (BUSCLK). I want to use TPM1 as base system timer. However, it does not seem the timer is using the value of the programmed bus clock (5.4MHz). FYI, I use the demo board which has 32KHz external crystal, and it seems the timer is still using the external clock. Another interesting point is that if I program using "Device Initialization" wizard on CW for ICGC1 value, it does not take it. Any idea why the programmed ICG values don't take effect? Thanks for any responses.