dac configuration

[pedropbr]

Posted on November 30, 2010 at 00:07

dac configuration

[lowpowermcu]

Posted on May 17, 2011 at 14:16 Thanks clive1 for this fast reply. It is little bit confusing but it seems to work in both cases. Herzlich, MCU Lüfter

[lowpowermcu]

Posted on May 17, 2011 at 14:16 I think I have found it :) In the configuration you are using channel2 and then when writing data you are using channel1 Try to change DAC_SetChannel1Data(DAC_Align_12b_R, 0x100); to DAC_SetChannel2Data(DAC_Align_12b_R, 0x100); MCU Lüfter

[pedropbr]

Posted on May 17, 2011 at 14:16

Oh, sorry, It was just a misspell.

I was doing it right. Still doesn't work. :(

[Tesla DeLorean]

Posted on May 17, 2011 at 14:16

With

DAC_SetChannel2Data(DAC_Align_12b_R, i); I am able to drive my own wave form.

[Tesla DeLorean]

Posted on May 17, 2011 at 14:16

int main(void)

{   GPIO_InitTypeDef GPIO_InitStructure;   DAC_InitTypeDef DAC_InitStructure;     TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;   /* Enable DAC and GPIOC clock */   RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO | RCC_APB2Periph_GPIOA, ENABLE);   RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC | RCC_APB1Periph_TIM2, ENABLE);   /* Configure PA.04/05 (DAC) as output -------------------------*/   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5;   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;   GPIO_Init(GPIOA, &GPIO_InitStructure); #if 0   /* TIM2 Configuration */   TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);   TIM_TimeBaseStructure.TIM_Period = 0xF;   TIM_TimeBaseStructure.TIM_Prescaler = 0xF;   TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;   TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;   TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);   /* TIM2 TRGO selection */   TIM_SelectOutputTrigger(TIM2, TIM_TRGOSource_Update);   /* DAC channel1 Configuration */   DAC_InitStructure.DAC_Trigger = DAC_Trigger_T2_TRGO;   DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_Triangle;   DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_4095;   DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;   DAC_Init(DAC_Channel_2, &DAC_InitStructure);   /* Enable DAC Channel2: Once the DAC channel2 is enabled, PA.05 is      automatically connected to the DAC converter. */   DAC_Cmd(DAC_Channel_2, ENABLE);   /* TIM2 enable counter */   TIM_Cmd(TIM2, ENABLE);   while (1)   {   } #else   /* DAC channel1 Configuration */   DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;   DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;   DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;   DAC_Init(DAC_Channel_2, &DAC_InitStructure);   /* Enable DAC Channel2: Once the DAC channel2 is enabled, PA.05 is      automatically connected to the DAC converter. */   DAC_Cmd(DAC_Channel_2, ENABLE);   while (1)   {         int i;         for(i=0; i<4096; i++)           DAC_SetChannel2Data(DAC_Align_12b_R, i);   } #endif   /* does not exit - kind of important */   return(1); }

[pedropbr]

Posted on May 17, 2011 at 14:16

Hi clive1,

it worked, you're the guy! thank you very much. :)

[lowpowermcu]

Posted on May 17, 2011 at 14:16

Hi rbpeter,

What was the tip to make it working ?MCU Lüfter

[pedropbr]

Posted on May 17, 2011 at 14:16

The solution clive1 proposed generates an AC signal in the exit.

To generate a DC signal, you just have to set a value between 0 and 4095 on the DAC like: DAC_SetChannel2Data(DAC_Align_12b_R, value); and you don't have to put it into the loop, once the value is loaded to the register, the DAC keeps generating the corresponding voltage. I was also debugging with the osciloscope in the wrong capacitor. Thank you all

[minhpc91]

Posted on December 04, 2014 at 14:03

Could you please check for me? It still doesn't work.

I'm using STM32F401VC Discovery.I dont see the define ''RCC_APB2Periph_AFIO'' in the library I'm using. Is there anything else I can use instead?I'm wondering if the PA4 and PA5 in my kit are out of order or not DAC1,2.Please help me!!int main(void){  GPIO_InitTypeDef GPIO_InitStructure;  DAC_InitTypeDef DAC_InitStructure;  /* Enable DAC and GPIOC clock */  RCC_APB2PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);  RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC , ENABLE);  // Configure PA.04/05 (DAC) as output -------------------------  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_5;  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;  GPIO_Init(GPIOA, &GPIO_InitStructure);  /* DAC channel1 Configuration */  DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;  DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;  DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;  DAC_Init(DAC_Channel_1, &DAC_InitStructure);  DAC_Init(DAC_Channel_2, &DAC_InitStructure);  DAC_Cmd(DAC_Channel_1, ENABLE);  DAC_Cmd(DAC_Channel_2, ENABLE);  while (1)  {        int i;        for(i=0; i<4096; i++)        {        DAC_SetChannel1Data(DAC_Align_12b_R, i);        DAC_SetChannel2Data(DAC_Align_12b_R, i);        }  }  return(1);}

[Tesla DeLorean]

Posted on December 04, 2014 at 14:59

This a four year old thread dealing with the STM32F1 parts, as I recall. The F4 pulls the AFIO functionality into the pin banks.

 RCC_APB2PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

Should be AHB1 not APB2