MPC5xxxのトピックRe: mcp5554 run code from ram

mcp5554 run code from ram

franme — Mon, 01 Feb 2021 09:18:11 GMT

hi i would you like to write with an external tool a code into ram and run it without change the memory flash. I write a simple code for blink a led( work fine into flash), i modify the lcf file to place this code in the ram, i use the ICDPPCNEXUS to write it. the code is correctly write into the ram( if i jump with PC i see the main code ), after i change the PC to jump on start and play run, the PC re jump into flash. if i load the PE algoritm, the code work fine from the ram. I don't know were is the problem. can help me

/* lcf file for MPC5554 (debug RAM version) */

/* 2 MB Flash, 64KB SRAM */

MEMORY
{
mail_box : org = 0x40000000, len = 0x00000100
resetvector: org = 0x40000100, len = 0x00000100
init: org = 0x40001000, len = 0x00001000
exception_handlers: org = 0x40002000, len = 0x00001000
pseudo_rom: org = 0x40003000, len = 0x00003000
internal_ram: org = 0x40006000, len = 0x00001400
heap : org = 0x40007400, len = 0x00000400 /* Heap start location */
stack : org = 0x40007800, len = 0x00000400 /* Start location for Stack */
}

SECTIONS
{
.__bam_bootarea: {} > resetvector

GROUP : {
.init LOAD (0x40001000): {}
.init_vle (VLECODE) LOAD (_e_init): {
*(.init)
*(.init_vle)
}
} > init

.__exception_handlers LOAD (0x40002000): {} > exception_handlers

GROUP : {
.text (TEXT) ALIGN(0x1000) : {}
.text_vle (VLECODE) ALIGN(0x1000): {
*(.text)
*(.text_vle)
}
.rodata (CONST) : {
*(.rdata)
*(.rodata)
}
.ctors : {}
.dtors : {}
extab : {}
extabindex : {}
} > pseudo_rom

GROUP : {
.__uninitialized_intc_handlertable ALIGN(0x10) : {}
.data : {}
.sdata : {}
.sbss : {}
.sdata2 : {}
.sbss2 : {}
.bss : {}
} > internal_ram
}

/* Freescale CodeWarrior compiler address designations */

_stack_addr = ADDR(stack)+SIZEOF(stack);
_stack_end = ADDR(stack);
_heap_addr = ADDR(heap);
_heap_end = ADDR(heap)+SIZEOF(heap);

/* Exceptions Handlers Location (used in Exceptions.c for IVPR initialization) */

EXCEPTION_HANDLERS = ADDR(exception_handlers);

/* L2 SRAM Location (used for L2 SRAM initialization) */

L2SRAM_LOCATION = 0x40000000;

Re: mcp5554 run code from ram

davidtosenovjan — Wed, 03 Feb 2021 10:06:50 GMT

No changes of linker file is needed, but user software should disable watchdog unless it will boot again from flash. Here you may see example for reference:

https://community.nxp.com/t5/MPC5xxx-Knowledge-Base/Example-MPC5554EVB-PinToggleStationery-CW210/ta-p/1121790

Re: mcp5554 run code from ram

franme — Thu, 04 Feb 2021 08:36:11 GMT

hi david thank you for your help I started from a similar example, and today I have use your example, I select the ram option and i load the elf with ICDPPCNEXUS -> load a single debug file the program load all and the PC value indicate the __start point. i run the code and after some time i stop it the new value of pc is in the flash. i don't know the problem. can you help me thanks

Re: mcp5554 run code from ram

franme — Thu, 04 Feb 2021 09:19:59 GMT

sometimes work if i load the algoritm to program the flash with PEmicro

Re: mcp5554 run code from ram

davidtosenovjan — Mon, 15 Feb 2021 11:13:14 GMT

Which address do you see in such case in the PC?

Does not it point to BAM address space i.e.0xFFFF_C000–0xFFFF_FFFF?

Re: mcp5554 run code from ram

franme — Mon, 15 Feb 2021 12:59:16 GMT

hi david

if i go with single step the pc jump to 0x0000f000

if I play go and after stop the pc value loop near to 0xFFFFFxxx

you have any idea

Thank you

Re: mcp5554 run code from ram

davidtosenovjan — Mon, 15 Feb 2021 13:21:34 GMT

At this point you could check SIU_RSR register to investigate reset reason. Probably device is reset for some reason.

Re: mcp5554 run code from ram

franme — Mon, 15 Feb 2021 15:37:35 GMT

hi david

I don't find the register RSR, I use your example in ram, i load it in ram the pc value is --start. but when i start the execution, the pc go to flash.

i don't use any scripts to reset o load in the ram. i disable the watchdog in the debug windows nothing else

i know the micro very little, is it necessary other configuration for run in the ram?

thank you

Francesco

Re: mcp5554 run code from ram

davidtosenovjan — Thu, 18 Feb 2021 16:51:39 GMT

If you are using PeMicro debugger, it should run debugger script at the beginning that is disabling watchdog, what I think is the root cause.