topic Re: S32K312: Fault Handler Entered When Calling Init Function(RAM Init Fails Despite Valid ROM Data) in S32K

S32K312: Fault Handler Entered When Calling Init Function(RAM Init Fails Despite Valid ROM Data)

jx938299598 — Sun, 17 Aug 2025 00:49:25 GMT

Hello, I'm encountering an issue with my project and would appreciate your assistance.

We are using the S32K312 chip and have adopted the official startup code provided with EB tools. The problem occurs when the program executes the MemAcc_Init function: this function calls MemFls_Init, but the program immediately enters the fault handler. The root cause appears to be an exception related to an unloaded global configuration variable.

Specifically, this global configuration variable maps the symbol address of MemFls_Init to an initialization pointer (InitPtr). When the fault occurs, the ConfigPtr (which points to this global configuration variable) becomes 0x0 (as shown in the call stack in Figures 1 and 2). Consequently, accessing InitPtr within this function attempts to dereference a null pointer, and the Program Counter (PC) trying to access address 0x0 triggers the fault interrupt.

Notably, the global array gunFlsInitAddress—which I added to track values—also shows all zeros during the fault. This confirms that the entire memory region storing these pointers remains uninitialized to 0x0. In contrast, Figure 3 shows the normal state of gunFlsInitAddress, where elements 2 to 4 contain the value 4693161 (hex: 0x479CA9), which corresponds to the correct address of MemFls_Init.

To further investigate, I used the T32 tool to dump memory blocks (Figures 4 and 5). The left panel (ROM) shows valid data, including the expected 0x479CA9 values, while the right panel (RAM) shows all 0x00 values during the fault—indicating a failure to properly load data from ROM to RAM.

I have attempted troubleshooting steps including:

Modifying the linker script (.ld file) to relocate the sector containing the initialization configuration structure to other memory regions.
Disabling the Cache functionality.

However, the exception persists. I would greatly appreciate any insights into identifying the root cause.

Re: S32K312: Fault Handler Entered When Calling Init Function(RAM Init Fails Despite Valid ROM Data)

danielmartynek — Mon, 18 Aug 2025 11:02:30 GMT

Hi @jx938299598,

Which version of the RTD are you currently using, and which compiler is used for the project?

Could you please verify that all compiler options are aligned with the RTD release notes?

Thank you

Re: S32K312: Fault Handler Entered When Calling Init Function(RAM Init Fails Despite Valid ROM Data)

jx938299598 — Mon, 06 Jul 2026 06:57:55 GMT

I am sorry not to notice your reply,and thanks for your reply, the problem has been solved.

The problem root caused by not using cache function in a standard way, when we closed the cache function, the problem will be not caused, however the system running slowly and will make influence on application function. And now our status in current project is using cache function with the mcu's MPU function opening, and we contact the NXP official AE to get a example on how to use cache function, and the problem has been closed permanently.

Thanks for your replay again.