Using TouchGFX without STM HAL

[MGiam.1]

Hi all,

I want to use TouchGFX without STM HAL. In my project that uses STM32L476, the code was just written with another library (libohiboard on GitHub). Our customer asks to add a display to this project, and I would use TouchGFX but without ST HAL. I try to generate a project with CubeMX, but I can't find the glue layer between GFX and HAL where I can change the HAL call.

Can you help me? Is it possible?

Thanks

Best regards

Marco

[MM..1]

I mean TouchGFX use hal parts only in generated target for dma2d and in

void TouchGFXGeneratedHAL::setTFTFrameBuffer(uint16_t* adr)
{
    LTDC_Layer1->CFBAR = (uint32_t)adr;
 
    /* Reload immediate */
    LTDC->SRCR = (uint32_t)LTDC_SRCR_IMR;
}
 
void TouchGFXGeneratedHAL::flushFrameBuffer(const touchgfx::Rect& rect)
{
    HAL::flushFrameBuffer(rect);
}
 
extern "C"
{
    void HAL_LTDC_LineEventCallback(LTDC_HandleTypeDef *hltdc)
    {
        if (LTDC->LIPCR == lcd_int_active_line)
        {
            //entering active area
            HAL_LTDC_ProgramLineEvent(hltdc, lcd_int_porch_line);
            HAL::getInstance()->vSync();
            OSWrappers::signalVSync();
            // Swap frame buffers immediately instead of waiting for the task to be scheduled in.
            // Note: task will also swap when it wakes up, but that operation is guarded and will not have
            // any effect if already swapped.
            HAL::getInstance()->swapFrameBuffers();
            GPIO::set(GPIO::VSYNC_FREQ);
        }
        else
        {
            //exiting active area
            HAL_LTDC_ProgramLineEvent(hltdc, lcd_int_active_line);
            GPIO::clear(GPIO::VSYNC_FREQ);
            HAL::getInstance()->frontPorchEntered();
        }
    }
}

Here is only one call HAL_LTDC_ProgramLineEvent(hltdc, lcd_int_active_line);, when you rewrite this to regs, target code is ok without hal.

Try explain what you need change?

[MGiam.1]

Hi,

thanks for your reply. I use STM32L476 and I would use FMC to communicate with the display.

Into TouchGFXGeneratedHAL I don't see any reference to FMC:

namespace {
    // Use the section "TouchGFX_Framebuffer" in the linker to specify the placement of the buffer
    LOCATION_PRAGMA("TouchGFX_Framebuffer")
    uint32_t frameBuf[(((240 + 7) / 8) * 128 + 3) / 4] LOCATION_ATTRIBUTE("TouchGFX_Framebuffer");
}
 
void TouchGFXGeneratedHAL::initialize()
{
    HAL::initialize();
 
    registerEventListener(*(Application::getInstance()));
    enableLCDControllerInterrupt();
    enableInterrupts();
    setFrameBufferStartAddresses((void*)frameBuf, (void*)0, (void*)0);
    /*
     * Set whether the DMA transfers are locked to the TFT update cycle. If
     * locked, DMA transfer will not begin until the TFT controller has finished
     * updating the display. If not locked, DMA transfers will begin as soon as
     * possible. Default is true (DMA is locked with TFT).
     */
    lockDMAToFrontPorch(true);
}
 
void TouchGFXGeneratedHAL::configureInterrupts()
{
}
 
void TouchGFXGeneratedHAL::enableInterrupts()
{
}
 
void TouchGFXGeneratedHAL::disableInterrupts()
{
}
 
void TouchGFXGeneratedHAL::enableLCDControllerInterrupt()
{
}
 
inline uint8_t* TouchGFXGeneratedHAL::advanceFrameBufferToRect(uint8_t* fbPtr, const touchgfx::Rect& rect) const
{
    //       Advance vertically                   Advance horizontally
    fbPtr += rect.y * lcd().framebufferStride() + rect.x / 8;
    return fbPtr;
}
 
uint16_t* TouchGFXGeneratedHAL::getTFTFrameBuffer() const
{
    return (uint16_t*)frameBuf;
}
 
void TouchGFXGeneratedHAL::setTFTFrameBuffer(uint16_t* adr)
{
    //setTFTFrameBuffer() not used for selected display interface
}
 
void TouchGFXGeneratedHAL::flushFrameBuffer(const touchgfx::Rect& rect)
{
  HAL::flushFrameBuffer(rect);
}
 
bool TouchGFXGeneratedHAL::blockCopy(void* RESTRICT dest, const void* RESTRICT src, uint32_t numBytes)
{
  return HAL::blockCopy(dest, src, numBytes);
}

I don't know where to modify to detach ST HAL.

[MM..1]

Here isnt STM HAL. HAL:: is cpp TouchGFX HAL layer .

FMC is custom type interface, then you need write your own code where you simply not use HAL. But why you plan FMC instead RGB?

[MGiam.1]

Yes, I know that there isn't STM HAL into this file... but with CubeMX I select the custom interface on TouchGFX, and when I activate the FMC the red point on TouchGFX come green! So, I think that there is just a connection between FMC and TouchGFX.

"FMC is custom type interface, then you need write your own code where you simply not use HAL."

Where can I put the code? I don't understand!

" But why you plan FMC instead RGB?"

What do you mean? The customer display is https://www.winstar.com.tw/it/products/graphic-lcd-display-module/display-lcd-240x128.html and I think it is the only way to manage this display. is it wrong?

[MM..1 · Accepted solution]

Complete example for custom FMC and SPI Display Interface | TouchGFX Documentation

[MGiam.1]

Thanks! I didn't see this section!