Freescale HCS12X port

gezab wrote on Friday, December 24, 2010:

Hi all,
Is the HCS12 port compatible with HCS12X processor cores? For instance the MC9S12XDP512MAG device?

markuskrug wrote on Wednesday, December 29, 2010:


as far as I know there is one major difference between the HCS12 and HCS12X. The pushed and popped values from the stack has a size of 1 Byte for the HCS12 and 2 Byte for the HCS12X.

Best Regards

abacus1980 wrote on Tuesday, January 04, 2011:

check out the unsupported ports/Freescale section of the freertos site.  there is a hcs12/12X port. 

i am trying to get it to work right now myself, but it will compile properly with


flag set in the linker or compiler command line options (using code warriror of course) .  the official HCS12 demo would not compile after much effort.

right now i am having problems with my ISRs not being called in CW which is not incrementing ticks.  so i can only get one task to run constantly :stuck_out_tongue_winking_eye:

let me know if you get processor expert to work with the ISRs setup in the unofficial port, i am pretty new to this but i hope it helps.

abacus1980 wrote on Tuesday, February 15, 2011:

I found the problem that prevents the demo to run for me anyways.

processor expert continually sets TIOS=0b10000001

set TIOS=0b00000001  and everything works.

to maintain compatibility with processor expert I use this command in the startup code

clrREG(TIOS, 128);