TouchGFX with SPI TFT

How did you create the project? Are you entering the TouchGFX main event loop ( HAL::taskEntry() )? If not then nothing will take elements off the vsync queue (And, as far as our OSWrappers are concerned, the queue is of length 1).

/Martin

Are you hitting a breakpoint in OSWrappers::waitForVsync() - You say it never returns but it's not clear to me if you mean that the code is actually being executed.

/Martin

Martin,

I created the project in CubeIDE and used the TouchGFX Generator. My project is in C so I created "gfxwrappers.h/cpp" to translate the necessary functions. Here are my two tasks:

void start_main_task(void *argument)
{
#include "gfxwrappers.h"
 
 for(;;)
 {
 vTaskDelay(pdMS_TO_TICKS(100));
 oswrappers_signalVSync();
 }
}
 
void start_gui_task(void *argument)
{
 /* Infinite loop */
 MX_TouchGFX_Process();
}

Inside OSWrappers::waitForVsync() there are two calls to osMessageQueueGet(). The first one, intended to clear the queue, returns as expected but the second call blocks forever. I've used breakpoints to confirm this. I also have a breakpoint inside TouchGFXGeneratedHAL::flushFrameBuffer and it is never reached.

The gui_task seems to be stuck at touchgfx::HAL::lockFrameBuffer(). Unfortunately, the debugger says there is "no source available" for any of the calls after touchgfx::HAL::backPorchExited() so I don't have much visibility into what's happening beyond that.

Please show me your OSWrappers

Hi @ebray​,

Please remove the call to acquire in initialize and get back to me.

/Martin

Also, i'd suggest driving TouchGFX not from another thread controlled by a scheduler, but from an actual signal from display, controller or hardware timer.

/Martin

Let's get to the bottom of this, @ebray​ ! :)