Moving from 9S08 to 9S12G

[DustyStew]

Hi

It looks as if the 9S12G is a perfect fit for changing over from a 9S08AW60. One would presume the 16 bit processor has higher throughput, but I am not so sure that will be true for all operations. I have not yet been able to decipher to 9S12's cycle counts.

Can anyone here share experience?

Thx

[iggi]

The number of bus cycles of all operations you can find in the S12XCPUV2 reference manual, Table A-2. Opcode Map  (see link below).

http://www.freescale.com/files/microcontrollers/doc/ref_manual/S12XCPUV2.pdf

The maximum bus clock frequency on S12G is 25MHz.

CodeWarrior for HCS12(X) MCUs v5.1 doesn’t have full chip simulation feature for full debugger support when S12G is used as target. We can enable it but it can only simulate instruction.

This is the method:

Press F5 to launch debugger,  in connection manager, hit “Abort”:

Then launch debugger, go to debugger menu “ component”, “Set connection…”, choose “full chip simulation”

Then go to debugger menu “File”, “Save Configurations”.

Close CW debugger.

Next time launch debugger again,  it will run in full chip simulation mode. please note, this is a kind of Instruction Set Simulator. We can’t utilize all the MC9S12G128 features with it.

In the Debugger, you can see number of cycles in the Register window.

Regards,
Ivan