MPC5646C RAM read using BAM

BorisB — Tue, 18 Jun 2024 08:17:29 GMT

Hi,

I am trying to read the internal RAM using the BAM module, via the UART

The problem is that there is a repeating pattern in the received file, that doesn't look correct.

This is the code i am using.

#define RAM_BASE 0x40000000 #define RAM_SIZE 256*1024 #define RAM_END RAM_BASE + RAM_SIZE int main(void) { int32_t i = 0, r = 0; uint32_t word = 0x00; InitHW(); InitializeUART(kBaud500000); /* Start the other core */ SSCM.DPMBOOT.R = (unsigned long)__start_p1; SSCM.DPMKEY.R = (unsigned long)0x00005AF0; SSCM.DPMKEY.R = (unsigned long)0x0000A50F; for (;;) { for (i = RAM_BASE; i < RAM_END; i+= 4) { word = *(uint32_t*) i; uart_print_int(word); } delay_100ms(1); } }

the pattern i am getting is:

00 00 20 7E 04 00 00 00 20 4E 04 00 00 00 10 0E 00 00 00 00 00 00 04 00 00 03 30 00 04 00 00 09 F0 DC 0F F0 F5 00 00 00 04 00 00 00 50 F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 02 60 00 00 00 00 00 70 CA 04 00 00 09 F0 D0 04 00 00 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 00 20 7E 04 00 00 00 20 4E 04 00 00 00 10 0E 00 00 00 00 00 00 04 00 00 03 30 00 04 00 00 09 F0 DC 0F F0 F5 00 00 00 04 00 00 00 50 F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 02 60 80 00 00 00 00 70 CA 04 00 00 09 F0 D0 04 00 00 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 00 20 7E 04 00 00 00 20 4E 04 00 00 00 10 0E 00 00 00 00 00 00 04 00 00 03 30 00 04 00 00 09 F0 DC 0F F0 F5 00 00 00 04 00 00 00 50 F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 02 70 00 00 00 00 00 70 CA 04 00 00 09 F0 D0 04 00 00 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 00 20 7E 04 00 00 00 20 4E 04 00 00 00 10 0E 00 00 00 00 00 00 04 00 00 03 30 00 04 00 00 09 F0 DC 0F F0 F5 00 00 00 04 00 00 00 50 F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 02 70 80 00 00 00 00 70 CA 04 00 00 09 F0 D0 04 00 00 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 00 20 7E 04 00 00 00 20 4E 04 00 00 00 10 0E 00 00 00 00 00 00 04 00 00 03 30 00 04 00 00 09 F0 DC 0F F0 F5 00 00 00 04 00 00 00 50 F0 00 00

Is this supposed to be normal, or i am getting something wrong. Its a new processor, an empty one, isn't it supposed to be empty.

Re: MPC5646C RAM read using BAM

lukaszadrapa — Thu, 20 Jun 2024 05:33:15 GMT

Hi @BorisB

RAM memory contains random data after power on. It must be initialized:

It's done in startup code like this:

stmw instruction is used - it writes all GPR core registers to RAM in a loop. That's the reason why you can see such pattern in the RAM.

Regards,

Lukas

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MPC5646C RAM read using BAM

Re: MPC5646C RAM read using BAM