Touch operation not working on custom pcb using stm32u5a9

[PatriciaQ]

Hello! I am struggling to get TouchGFX fully working on my custom PCB using a STM32u5A9ZJT (LQFP144). Everything compiles correctly and uploads. I can see my Screen1 background and button on my screen so at least that is working. But when I touch my button it does not transition to the next screen (as it does in the TouchGFX simulator when I run this code). Using my debugger i can see that the touch is triggering the external interrupt, and the coordinates are correct in STM32TouchController::sampleTouch but the expected screen transition never occurs. When comparing the IOC files between my working demo project and custom project, I noticed I did not have DCACHE enabled, but when I enable DCACHE I get a HardFault right after registering a touch.

 

Setup background -- I began development with the Riverdi_50STM32u5a9. This was available as a board option on TouchGFX so I was able to create my project through TouchGFX first. However, the STM32u5 used in our custom PCB was not a board option within TouchGFX and was not pin compatible with any of the options that did exist. So I created my project starting first with CubeMX then added TouchGFX as an add-on package.

 

I copied over the missing functions from STM32TouchController.cpp/hpp that TouchGFX generates in my Riverdi demo project over to my custom project. The screen we are using is the same as in the demo board so I was able to copy over all the configuration settings of the frame buffer, ltdc, etc. in CubeMX.

 

Is there a noticeable gap in my implementation or setup? Has anyone experienced a fault when mapping a touch into a GUI update? I'm new to the STM and TouchGFX realm. I can't even follow how SampleTouch triggers the button handler... any insight would be appreciated!

 

STMCubeIDE version: 1.16.0

TouchGFX version: 4.24.1

Board: STM32u5A9ZJT (LQFP144)

[Osman SOYKURT]

Hello @PatriciaQ ,

Screen transition not performing could be another issue no related to touch. Could you just try to press on a button and see if that reacts? Normally, when you press on button you have 2 different assets depending of the state of your button:

You can alternatively try to add a box to your application and configure an interaction like bellow, just to see if the coordinate of your touch are correct and that the button actually can trigger something :

If that does work I recommend then to use a flexbutton with the size of your entire screen and do the same (change box color for instance). If that do something I would definitely suspect coordinate issue.

To check if your click event has the correct coordinates, you could try to add this code in your ScreenView.cpp

void ScreenView::handleClickEvent(const ClickEvent& event)
{
 int x = event.getX();
 int y = event.getY();
}

And then when debugging, try to compare these values with what you got from your sampleTouch.

[PatriciaQ]

Hi Osman,

 

Thank you for your quick reply and the suggestions. Good thinking on verifying the coordinates first before worrying about the screen transition.

 

Looks like I am actually always getting a HardFault upon touching the screen (not just when I enable DCACHE). If I run my debugger and set my breakpoint within sampleTouch the I2C Receive works and the X_Touch and Y_Touch coordinates are read successfully, but once I step past that function I see a "No source available for touchgfx::HAL::tick()" then it enters the HardFault loop. 

 

This tick() looks to be called from the HAL.hpp backPorchExited() function

 

When I do not touch the screen, and set my breakpoint here this tick() function gets called periodically and runs without issue. Do you have any suggestions on what could be causing this? I've been looking around the forums and haven't found anything that has helped.

 

Is it possible that there is something wrong at the build stage since I am not starting the project in TouchGFX and the folder structure is slightly different? Or would that usually result in a build/compiler/linker error? I am attaching the build output in case it could be helpful. 

[PatriciaQ]

Update: I fixed the HardFault.

One of the things I missed in getting my CubeMX generated project ready to interface with TouchGFX were the STM32U5A9NJHXQ_FLASH.ld and _RAM.ld files

^ my custom PCB project's FLASH.ld file is on the left and the working demo project on the right. Was missing some configuration for the frame buffers 

 ^ ram.ld file was missing larger heap and stack size

I copied over the differences (hoping the difference between the NJHXQ and my ZJTXQ doesn't impact the flash and ram... does it?). The system now responds to my on-screen button presses; however, the screens have now gone black. Only the Box elements are showing up.

I haven't seen much info about how touchgfx memory is handled. Where is that controlled? Are there any resources available or suggestions you may have?

Thanks!

[PatriciaQ]

Just wanted to clarify that "screens have now gone black. only the box elements show up" I mean that the Touchgfx background screen images are no longer appearing. 

I know the box elements are simple to generate so it isn't stored as a separate image file. Is there a way of knowing where touchgfx is storing these image files? 

[Osman SOYKURT]

Hello @PatriciaQ ,

I recommend you to read our documentation to know more about how we use memory. These 2 pages will help you to understand what are the different type of memory (RAM/Flash) and what they're used for.

https://support.touchgfx.com/docs/basic-concepts/embedded-graphics

https://support.touchgfx.com/docs/basic-concepts/memory-usage

What you'll probably need to check is your linker script (STM32U5A9NJHXQ_FLASH.ld) and modify it. Make sure your assets are placed in the correct memory region. You haven't precised if you were using external memory, could you give more details about your RAM and Flash available ?

By default images are located in external RAM in TouchGFX.

You can change the default region from the "Default Image Configuration" panel in the "Config" Tab, or individually every images in the "Image" Tab like this :

[PatriciaQ]

Thank you Osman for the resources and insight about where to designate the storage of the TouchGFX images! Switching the Default Image Configuration section to Internal Section fixed the black screen issue. Our board actually does not currently have external flash but we will likely be adding it after reading through the memory documentation. 

 

If anyone is stumbling across this forum thread and is having issues with TouchGFX on their custom board after using CubeMX to generate their code instead of starting through TouchGFX, make sure to check your linker files and the TouchGFX image settings tab.