I am moving over from the ancient PEMicro HCS08 assembly development environment to CW and C. I can run the PEMicro debugger and S08SH8 at 20MHz bus speed but in CW I can't seem to configure the ICS to go above 16MHz. I have already used CW and C for slower bus applications but this project needs 20MHz.
Please look into AN2616, chapter 4.8 (Set Clock Frequency) which explains the formula to calculate bus frequency as well as an example code on how to configure the clock in C.