Transaction error trying to use DMA to write to GPIO

[Elin]

I've been trying to set up a timer and DMA to run a synchronous parallel bus onto a GPIO. The timer works great but the DMA keeps failing with a transaction error interrupt and disables the stream. This is on an STM32F413 chip and using TIM2_CH1 as a PWM output and DMA1 Stream 1 connected to TIM2_UP event. The DMA is configured as below:

  static uint16_t _waveform[2];
  _waveform[0] = 0x0555;
  _waveform[1] = 0x0AAA;

  LL_DMA_SetChannelSelection(DMA1, LL_DMA_STREAM_1, LL_DMA_CHANNEL_3);
  LL_DMA_SetDataTransferDirection(DMA1, LL_DMA_STREAM_1, LL_DMA_DIRECTION_MEMORY_TO_PERIPH);
  LL_DMA_SetStreamPriorityLevel(DMA1, LL_DMA_STREAM_1, LL_DMA_PRIORITY_VERYHIGH);
  LL_DMA_SetMode(DMA1, LL_DMA_STREAM_1, LL_DMA_MODE_CIRCULAR);
  LL_DMA_SetPeriphIncMode(DMA1, LL_DMA_STREAM_1, LL_DMA_PERIPH_NOINCREMENT);
  LL_DMA_SetMemoryIncMode(DMA1, LL_DMA_STREAM_1, LL_DMA_MEMORY_INCREMENT);
  LL_DMA_SetPeriphSize(DMA1, LL_DMA_STREAM_1, LL_DMA_PDATAALIGN_HALFWORD);
  LL_DMA_SetMemorySize(DMA1, LL_DMA_STREAM_1, LL_DMA_MDATAALIGN_HALFWORD);
  LL_DMA_DisableFifoMode(DMA1, LL_DMA_STREAM_1);
  LL_DMA_SetPeriphAddress(DMA1, LL_DMA_STREAM_1, (uint32_t)&GPIOD->ODR);
  LL_DMA_SetMemoryAddress(DMA1, LL_DMA_STREAM_1, (uint32_t)_waveform);
  LL_DMA_SetDataLength(DMA1, LL_DMA_STREAM_1, 2);

  LL_TIM_EnableDMAReq_UPDATE(TIM2);

All of GPIOD is configured as outputs and as soon as DMA1 receives the DMA request from the timer I get an interrupt with TEIF1 set. I've been looking around at various similar solutions and I don't think I'm doing anything wrong?

[mƎALLEm]

Hello @Elin and welcome to the community,

Please refer to this thread. The OP is using DMA2.

[Elin]

Yes, I was looking at that post earlier and comparing with my own code and from what I can tell it's pretty much identical except different DMA and Timer. Surely this should work with DMA1 as well?

[TDK · Accepted solution]

> Surely this should work with DMA1 as well?

There is no link between DMA1 and AHB1, where GPIOD is located. Use DMA2.

[mƎALLEm]

Use DMA2 not DMA1. This is what I've indicated in my post.

[Elin]

I see now. I was trying to find something like that bus matrix table before but didn't know where to look. That makes sense then why it wouldn't work. Now I need to modify our hardware since it's locked into TIM2 which can't be used with DMA2.

Thanks for the quick help anyway!