stm32f407 Programming parallelism error firing for no reason

[abdosalm]

I am using the stm32f4 discovery board and writing bare-metal drivers for the embedded flash memory.

I am facing a strange problem when writing to flash memory, to save you time for reading code and when the error happens, here is the status:

Before Error:

FLASH_CR register:

FLASH_SR register:

as you can see, PSIZE if configured correctly, but when this line of code run:

*global_pu32MemWriteVar = *(uint32_t *)argConst_pu8WriteData;

or in assembly it will be:

 416                          *global_pu32MemWriteVar = *(uint32_t *)argConst_pu8WriteData;
08000762:   ldr     r3, [pc, #216]  ; (0x800083c <HAL_FLASH_Write+604>)
08000764:   ldr     r3, [r3, #0]
08000766:   ldr     r2, [r7, #4]
08000768:   ldr     r2, [r2, #0]
0800076a:   str     r2, [r3, #0]

I see PGPERR: Programming parallelism error get raised even though PSIZE is configured correctly and PG bit is set to 1.

After Error:

FLASH_CR register:

FLASH_SR register:

[TDK]

What values are in r2 and r3 when that line executes?

One of your screenshots has PG=0. It needs to be PG=1.

[abdosalm]

sorry, I posted the incorrect screenshot, it's just I have some problems dealing with the web editor of ST forums, anyways, it's 1 (I made sure it's 1), it was just incorrect screenshot

[TDK · Accepted solution]

What about r2 and r3? Specifically looking to check if r3 is word-aligned.

[abdosalm]

sure,

this is the content of R3 before STR command:

and this is the content of R2 before STR command:

[abdosalm]

thanks, a lot.

I discovered that the address I was trying to write to isn't word aligned