Cortex-R52+ Undefined exception

Hi

R52+ goes to undefined exception after debug exception. Here are the instructions leading to the exception:

Issue: The debug exception occurs for address 0x28078480 (MOV R0, #01). We found the address leading to the undefined exception is 0x28078482 according to the lr register in the undefined handler.

We tried to save CPSR in front of MOV R0, #0x1, after adding some instructions, the undefined exception never happens. If set the address for generating debug exception to 0x28078482, the undefined exception never happens.

Could you give some clues for the cause of the undefined exception ?

BR, Grace