topic Re: [MPC5744P]FCCU+SWT in MPC5xxx

[MPC5744P]FCCU+SWT

Sxhdjw — Tue, 07 Apr 2026 02:43:34 GMT

Dear NXP officers:

Hi, i got trouble with the FCCU_mpc5744p example u offered in S32DS .

1. when i program the chip and press SW1 , the alarm led begins shining for period time since FCCU fault has worked and system switch to alarm status. when i try to press SW2 to clean fault, the alarm led turn off in a moment. But when i release the SW2, the alarm led shine again.so why?

here's some details :I change SW1 ,SW2 and alarm led because I didn't use the official core board. by the way , i also change the SIUL_ISR channel to 243 in intc_SW_mode_isr_vectors_MPC5744P.c. before this step , if i didn't change the channel ,the led even didn't work.
2. I also try to use the software watch dog for my project. According to the short reset example from the forum . it truly works to reset but it didn't back to _start from the reset . Besides i cant watch any info from the debugger cauese the core is offline.

Re: [MPC5744P]FCCU+SWT

petervlna — Tue, 07 Apr 2026 06:25:38 GMT

Hello,

I have looked at the main.c you have provided. It looks like majority of FCCU setting is copied from mine codes.

Unfortunately author of the example, is no longer in NXP so I can't ask him about the example.

Whole example seems to me awkward.

However I can guide you quite easy trough the process.

Write me what you really want to do with FCCU and I can guide you.

Also I have written some applicaiton notes along with examples SW for MPC5744P FCCU.

You can start by reading them and looking into examples to understand how FCCU works first:

https://community.nxp.com/t5/MPC5xxx-Knowledge-Base/MPC574xP-FCCU-configuration-guide/ta-p/1105448

Best regards,

Peter

Re: [MPC5744P]FCCU+SWT

Sxhdjw — Wed, 08 Apr 2026 01:31:42 GMT

Hi,

Thanks for reply, I actually want to do the software watchdog function(SWT) . Besides, I have referenced the sample code "Example MPC5744P SWT Short reset GHS614". And in fact its really works on my mpc5744p device .But, as what i say in the last inquire, the SWT works but it didn't go into _start and the cpu hanged up , i cant read any info from the s32 debugger. so i guess if there is any problem in FCCU after reset because it didn't go from the SAFE status to NORMAL status . To verify my guess , i try to use ur FCCU example to prove it . That's all . Is there any advice offer for me? I truly need the SWT in my project.