Code Warrior Banked Freescale HCs12

electropw wrote on Friday, August 27, 2010:

In the Port.c file where the ‘pxPortInitialiseStack’ function is defined, the value for the CCR, (line 152), should be changed **to 0x40 **from 0.

Setting the CCR to zero enables the XIRQ.

If the XIRQ functionality is wanted it would be more appropriate to enable it specifically somewhere else, since it is a one time operation and once enabled cannot be turned of again until a reset is performed.


davedoors wrote on Friday, August 27, 2010:

Sounds like a good thing to add to the feature request tracker. I know its not a feature request but it will allow it to get added to the todo list (doesn’t mean it will actually get done, but it won’t get lost).

electropw wrote on Sunday, August 29, 2010:

I’ll do that.

We should also consider the STOP instruction control bit (bit 8 of the CCR).
The current initialization code turns it on as well, however it is possible to turn the it off again under s/ware control.
If the default initialization code keeps it turned off then each task must turn it on if it is wanted.

To keep it turned off by default, the CCR should be initialized to 0xC0.