MPC5xxxのトピックRe: MPC5777C FCCU Initialization Exception Inquiry

MPC5777C FCCU Initialization Exception Inquiry

kwru — Tue, 30 Sep 2025 01:30:50 GMT

Hello,
I am currently using the FCCU with the MPC5777C.
When initializing the FCCU, after resetting NCFS_CFG[0] and NCFS_CFG[1], if I then initialize NCFS_CFG[2] to 0x0000, an Exception occurs. I checked NCFS_CFG[2] and found that it contains ECC-related registers. Could the Exception be caused while initializing these registers?
I would like to know if it is normal for an Exception to occur during initialization.

Re: MPC5777C FCCU Initialization Exception Inquiry

petervlna — Tue, 30 Sep 2025 06:49:46 GMT

Hello,

if I then initialize NCFS_CFG[2] to 0x0000, an Exception occurs.

I am not familiar with your configuration, but configure reset reaction on fault. So you exception is not linked to this change.

petervlna_0-1759214721032.png

Which kind of exception you are getting? IVORxx number?

I would like to know if it is normal for an Exception to occur during initialization.

Exception is never normal state. It means you have some issues in access, etc...

Please refer to the core reference manual for details:

7.8 Exception recognition and priorities

petervlna_1-1759214973879.png

Best regards,

Peter

Re: MPC5777C FCCU Initialization Exception Inquiry

kwru — Tue, 30 Sep 2025 08:13:17 GMT

There is nothing special about the initialization code. The FCCU is initialized with reference to the reference code, as shown below. The part where an exception occurs is indicated in the comments.

FCCU.TRANS_LOCK.R = 0xBCU;
FCCU.CTRLK.R = 0x913756AFU
FCCU.CTRL.R = 0x1U;

FCCU.NCF_E[0].R = 0xFFFFFFFFU;
FCCU.NCF_E[1].R = 0x7FFFU;

FCCU.NCFS_CFG[0].R = 0x0000U;
FCCU.NCFS_CFG[1].R = 0x0000U;
FCCU.NCFS_CFG[2].R = 0x0000U; // Exception IVOR1 Occured!!!

FCCU.CTRLK.R = 0x825A132BU
FCCU.CTRL.R = 0x2U;

Re: MPC5777C FCCU Initialization Exception Inquiry

petervlna — Wed, 01 Oct 2025 07:27:38 GMT

Hello,

Hmm, I see no issue in the code of FCCU itself.

Do you step debug the code or you run it over the FCCU config.

As FCCU config mode is guarded by config watchdog and you will get timeout if you try to debug configuration code. But such will not drop IVOR1.

If you see IVOR1, then check the details of the exception in MSCR register

petervlna_0-1759303527243.png

petervlna_1-1759303549405.png

I do not see this issue linked to FCCU, Rather some access restriction.

Identify the reason for IVOR1 then you will see where to look.

Best regards,

Peter