MPC5777C Slower software execution without debugging

[darq]

Hello,

I have discovered one illogical behavior of our node. When debugging, the software executes much faster then without debugging. I am using s32 design studio with PE-Micro Universal debugger connected via JTAG. I have checked this several times just to make sure. The setup for both situations is the same, the software is the same, debugger is always connected via JTAG. The only difference is that debugging session is either started in s32 design studio or not. The signals on attached pictures are from top: 1ms task execution (yellow), 10ms task execution (pink), 100ms task execution (blue), crc calculation loop (green).

Does anyone have any idea what could be the cause? Where could i look to investigate further?

Best regards

[davidtosenovjan]

Hi, have you checked internal flash configuration (PFLASH_PFCRx registers)? By default this is not set to optimum setting and this could be set by debugger's flash programming script.

I would point out to AN5191, section 4.1:

https://www.nxp.com/docs/en/application-note/AN5191.pdf

[darq]

Hello,

Any ideas? As of now the core 1 have to be disabled until root-cause is found?

Best regards

[darq]

Hello,

Thank you for your response, i will look into it. After further investigation it seems like the issue is related to core 1. The software on core 0 was enabling core 1 but software for core 1 was not flashed which i assume would result in some exception on core 1(invalid instruction?). When the function enabling core 1 was commented out there was no noticeable difference between software execution on core 0 when debugging and not. I will just mention that i was debugging only core 0. Any ideas how this could be explained?

Best regards