Interrupt priority in MC9S12DJ128

[jtpark]

Hello,

I am using a MC9S12DJ128  for BCM.

Some problem occurred during CAN interface.

When I tried interrupt in "CAN0 errors", "CAN1 Transmit" didn't work.

Other interrupt was working well.(Timer, etc.)

Where can I check the interrupt priority?

Thanks.

[lama]

Hi,

An Interrupt priority is given by order in the vector table. There is no possibility to chang interrupt priority with exeption than there is one interrupt from I bit maskable interrupt which priority can be put higher from other I-bit maskable interrupts by means of register HPRIO.

There are two application notes which ususally solves issue with interrupts.

Issues with interrupt priority and nesting interrupts solves.

• A Software Interrupt Priority Scheme for HCS12 Microcontrollers
  http://www.nxp.com/files/microcontrollers/doc/app_note/AN2617.pdf
   

Issues with clearing flags when they all are in the same register.

• Clearing and Disabling Interrupt Flags
  http://www.nxp.com/files/microcontrollers/doc/app_note/AN2554.pdf
   

So it looks like you are still going in the loop into CAN0 and all other higher interrupts which avoid you to serve CAN1 interrupts.

Best Regards, Ladislav