allocation of global variable SD-RAM external memory.

[thyu]

The 'HAL_SDRAM_Write_8b' and 'HAL_SDRAM_Read_8b' functions were confirmed using STM32H723ZGT6 and IS42S16320D-6TLI.
(Check variable value changes with STM32CubeIDE's Memory Viewer and LiveWatch, no hardware problems)

All internal RAM has been used to implement the current application.
Additional feature implementation requests require variable allocation and access to external RAM.

I reviewed the STM32CubeH7 example and applied it to my project, but encountered a HardFault Handler.
(Modify STM32H747XIHX_FLASH.ld file in my Project)

Please let me know if there is anything else I need to check.
- Example path: \STM32Cube\Repository\STM32Cube_FW_H7_V1.11.1\Projects\STM32H747I-EVAL\Examples\FMC\FMC_SDRAM_DataMemory\STM32CubeIDE\CM7

 

Build Analyzer - Memory Regions

 

HardFault_Handler

 

Debug Message

STMicroelectronics ST-LINK GDB server. Version 7.5.0 Copyright (c) 2023, STMicroelectronics. All rights reserved. Starting server with the following options: Persistent Mode : Disabled Logging Level : 1 Listen Port Number : 61234 Status Refresh Delay : 15s Verbose Mode : Disabled SWD Debug : Enabled InitWhile : Enabled Waiting for debugger connection... Debugger connected Waiting for debugger connection... Debugger connected Waiting for debugger connection... ------------------------------------------------------------------- STM32CubeProgrammer v2.15.0 ------------------------------------------------------------------- Log output file: C:\Users\thyu\AppData\Local\Temp\STM32CubeProgrammer_a05560.log ST-LINK SN : 49FF6E067789485425281567 ST-LINK FW : V2J42S7 Board : -- Voltage : 3.27V SWD freq : 4000 KHz Connect mode: Under Reset Reset mode : Hardware reset Device ID : 0x483 Revision ID : Rev Z Device name : STM32H72x/STM32H73x Flash size : 1 MBytes Device type : MCU Device CPU : Cortex-M7 BL Version : 0x93 Memory Programming ... Opening and parsing file: ST-LINK_GDB_server_a05560.srec File : ST-LINK_GDB_server_a05560.srec Size : 64.81 KB Address : 0x08000000 Erasing memory corresponding to segment 0: Erasing internal memory sector 0 Download in Progress: File download complete Time elapsed during download operation: 00:00:01.737 Verifying ... Download verified successfully

 

 

[Tesla DeLorean]

Your SystemInit() code needs to bring up the clocks, PLLs and SDRAM so code in startup.s can initialize the statics. Doing it in main() is too late.

The HardFault_Handler indicates that the memory you are touching is not functional.

[mƎALLEm]

Hello,

You need to initialize the memory first (GPIO and FMC) in SystemInit() / system_stm32h7xx.c.

If you look at system_stm32h7xx.c provided in one of the STM32H747I-EVAL examples you can find the following:

So look at SystemInit_ExtMemCtl() implementation. You need to activate de definition DATA_IN_ExtSDRAM.

Also there is an example how to locate the global variables in the external SDRAM in x-cube-perf-h7  related to the AN4891 STM32H72x, STM32H73x, and single-core STM32H74x/75x
system architecture and performance

Look at the project config 6 where the code is executed in ITCM and all variables are located in SDRAM:

Advice: before starting to relocate your variables in SDRAM, you need to do some read/write tests to validate that the SDRAM access is correct and you don't get any read/write issues.

Hope it helps.

 

[thyu]

Let's try it that way.

[mƎALLEm]

Hello @thyu ,

Did you already solve your issue? if yes, please close this thread by clicking on Accept as solution the comment that answered your question.

Thank you.