BUG: CubeMX enables unused channel on dual-channel DAC

[EHabi.1]

I configure STM32F767I(G-I)Tx via CubeMX.

I enabled ADC_IN4 and DAC_OUT2 on dual-channel DAC.

ADC_IN4 shares pin with DAC_OUT1. Even though DAC_OUT1 was not enabled in CubeMX I can see it applies voltage on the pin breaking ADC reading,

This can be solved by adding

sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;
HAL_DAC_ConfigChannel(&hdac, &sConfig, DAC_CHANNEL_1);

to MX_DAC_Init().

Which means CubeMX enables DAC channel which was not configured/enabled in GUI.

IMO, it's better to be fixed at CubeMX level than adding user code which disables unused DAC channel.

[Sara BEN HADJ YAHYA]

Hello @EHabi.1​ ,

Thanks for your feedback,

Which CubeMX version are you using ? and does your code contain the following lines in DAC init when DAC_OUT1 is Disabled in CubeMX GUI ?

  sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_ENABLE;
  if (HAL_DAC_ConfigChannel(&hdac, &sConfig, DAC_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }

Thanks,

Sara.

[EHabi.1]

Hi Sara,

I'm on CubeMX 6.3.0 and my DAC init does not contain DAC_OUTPUTBUFFER_ENABLE

for channel 1 (I also checked the whole application code). So it looks like if it's not disabled it will be enabled by default.

[Sara BEN HADJ YAHYA]

Hello @EHabi.1​ ,

I don't think that this issue is related to CubeMX, there is no lead in the generated code nor in the graphical user interface that points to this issue so I am adding @Imen DAHMEN​  to the loop for review and provide a status update about this issue.

Sara.