Stuck on _exit() in syscalls.c with void STM32TouchController::init() - STM32F469I-DISCO

[Kneepatch]

I can't get my display to work after I enabled the uSD card on my STM32F469I-DISCO, it just sits at a black screen. When I ran the debugger, this is the call stack it shows, stuck on _exit() in syscalls.c:

Is there an easy way to determine what conflict is happening when I add my uSD card? Full disclosure: using TouchGFX to generate this project file in STM32CubeIDE.

[Iris-DM]

I've got exactly the same issue this afternoon.

CubeMX Ver 6.13.0

TouchGFX Ver 4.24.1

Running on STM32H747I-Disco with different screen. Instead of the 800x480 screen that comes with the dev kit, I've got a 5" 720x1280px display. The TouchGFX & STM32CubeIDE projects were built from the blank discovery kit project in TouchGFX designer and then modified in CubeMX to meet the correct specs for the screen. 

[Pavel A.]

So it looks that BSP_TS_Init() returned not TS_OK. Debugger is your friend.

[Kneepatch]

I've been going through the debugger but am still unable to determine the issue. BSP_TS_Init() returns that the touchscreen is not found (return code 3). Are there any other debugger features you are referring to that can help other than stepping through the code line by line? Any good tutorials that you can recommend? I found this series, but it really doesn't go through the debugger basics in STM32CubeIDE: STM32CubeIDE Advanced Debug Features: Part 1

[Pavel A.]

> other than stepping through the code line by line

You can place breakpoints in strategic places. Breakpoints can have pass counts (for example break only after N iterations) and expressions. STM32F4 and 'H7 have even more debug features via the ITM module.

[Flemming Gram CHRISTENSEN]

Check the GPIOs used. Is there an overlap between the I2C and the SDCard?

Some of the GPIOs used in the F746 BSP is seen in MX others are just used in the code, so it can be little difficult.

The schematic of the board can be a help.

Best Regards

[Kneepatch]

I had the same thought myself, but when I look at CubeMX and at the schematic, I don't see any conflicts (for what it's worth, I'm using the STM32F469I-DISCO evaluation board).

MicroSD:

I even checked the clock settings before/after adding the uSD card and those look the same, so I am at a loss as to why I am getting a TS_DEVICE_NOT_FOUND status when trying to do the I2C read:

[Flemming Gram CHRISTENSEN]

Ok. 

My next step would be to single-step with the debugger through the touch init code and make note of what is received from I2C. Try it without SDcard enabled and then with. Could give a clue on the problem.