Posted on October 30, 2016 at 09:09I'm using the 32F334C8 Pa4 dac1_out1 channel.However, buffer is not working. Here is my code,
void DAC_Config(void)
{
DAC_InitTypeDef DAC_InitStructure;
/* Configure DAC1 OUT1 ******************************************************/
/* GPIO Periph clock enable */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
/* Configure PA4 (DAC1_OUT1) as analog */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* DAC1 Periph clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC1, ENABLE);
/* DAC1 deinitialize */
DAC_DeInit(DAC1);
/* Fill DAC InitStructure */
DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;
DAC_InitStructure.DAC_Buffer_Switch = DAC_BufferSwitch_Disable ; // DAC_BufferSwitch_Enable;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bit0;
/* DAC Channel1 Init */
DAC_Init(DAC1, DAC_Channel_1, &DAC_InitStructure);
// DAC_Init(DAC2, DAC_Channel_1, &DAC_InitStructure);
/* Enable DAC Channel1 */
DAC_Cmd(DAC1, DAC_Channel_1, ENABLE);
/* Set DAC Channel1 DHR register: DAC1_OUT */
// DAC_SetChannel1Data(DAC1, DAC_Align_12b_R, (uint16_t)CurrentSenseTab[0]);
}
I think i can't open the buffer because i always see voltage at PA4 out pin. In programming manual i found that:
The DAC1 channel 1 comes with an output buffer that can be used to reduce the outputimpedance on DAC1_OUT1 output, and to drive external loads directly without having toadd an external operational amplifier.
I hope i'll solve that problem. Thanks
#stm32f334
