I'm having a very strange issue. My C code worked like a charm, until this morning. And since this morning, it stops every time in unknown exception routine.
I'm using interrupts, quite a lot of them, but they are all handled properly. I have read FAQ:How do I resolve unknown exception and several posts regarding this subject, but unfortunately that didn't solve my issue.
My "symptoms" are: SEQSTAT = 0xE021 (HWERRCAUSE = 0x3 - External Memory Addressing Error and EXCAUSE = 0x21 - Undefined Instruction). I'm not using any External Memory, just L1 and L2. ASYNC Banks 0 and 1 are enabled, but they are not used, if I comment initialization of these banks, problem stays. $RETX sends me to some unknown address.
This is a custom board, so it might happen that there is some hardware issue, but I'd like to know what could cause this.
I'll provide other information if it is necessary.
Thank you in advance,