Hi, I need a PWM function to use with a frequency of as low as a minute or two. For example, a freq of 1 minute would provide a 30 secs on/30 secs off with a 50% duty cycle. I'm using a 32.768kHz external crystal attached to the XTAL pins, and have a bus frequency of 4MHz. Unfortunately, dividing the clock by 128 and doing a full count in the TPM counter 0xFFFF does not provide a sufficiently long time period.
There is a statement in my user manual that an internal "XCLK" could be used. After reading what I could find in this forum, I still cannot figure out if there's a way to provide a lower clock freq to the TPM without changing the bus clock frequency. If using the "XCLK" is an option, any suggestions about what registers to alter to provide a lower clock freq for the TPM ? I am using the HCS08LG32 (C coding). Thanks.