8-bit MicrocontrollersのトピックRe: Illegal BP error MC9S08

Illegal BP error MC9S08

b_rad — Tue, 30 Aug 2011 00:51:31 GMT

Hi,

I'm implementing SPI communications using the MC9S08GT16A. The code has been working perfectly for ages and now, all of a sudden, im getting an illegal BP error.

I keep getting the error even with the watchdog disabled and no interrupts present in my code.

If its not an unmapped interrupt or the watchdog then the other two options are an illegal address or a stack overflow, right?

Ive made the stack as large as possible.

So, how do I check if its trying to access an illegal address, and if so, fix that?

Thanks

Re: Illegal BP error MC9S08

rocco — Tue, 30 Aug 2011 03:00:03 GMT

b-rad wrote:

If its not an unmapped interrupt or the watchdog then the other two options are an illegal address or a stack overflow, right?

There are other things that can cause that problem, like mis-jumping to an address that does not contain valid code, or jumping to valid code but not aligned correctly to the instruction. If your using C, check for un-initialized pointers. In assembler, there are dozens of things that can cause that. I think I've done most of them.

Re: Illegal BP error MC9S08

bigmac — Tue, 30 Aug 2011 11:10:10 GMT

Hello,

Do you happen to be using full chip simulation (FCS) mode? If so, the SPI code may not operate as intended. Best to use the actual hardware when testing your SPI code.

Regards,

Mac