Question
Switching pin between ADC and General IO
Posted on April 09, 2014 at 18:53
Hi All,
What I would like to do is when I receive a CAN bus message with data equal to ''12'' I will configure GPIOB Pin 0 to an Analog input, and when the data is 11 it will be reconfigured to an General purpose I/O. &sharpdefine ADC1_DR_Address ((uint32_t)0x4001244C)__IO uint16_t ADCConvertedValue[5]; void Port_Config(void){ RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_GPIOA| RCC_APB2Periph_GPIOB, ENABLE); /* Configure PA.0,1,2,3 as analog input -------------------------*/ GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN; GPIO_Init(GPIOA, &GPIO_InitStructure);/* Configure PB.0 as Output -------------------------*/ GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; GPIO_Init(GPIOB, &GPIO_InitStructure); /* DMA1 channel1 configuration -------------------------------*/ DMA_DeInit(DMA1_Channel1); DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address; DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&ADCConvertedValue; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; DMA_InitStructure.DMA_BufferSize = 4; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; DMA_Init(DMA1_Channel1, &DMA_InitStructure); /* Enable DMA1 channel1 */ DMA_Cmd(DMA1_Channel1, ENABLE); /* ADC1 configuration -----------------------------------------*/ ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; ADC_InitStructure.ADC_ScanConvMode = ENABLE; ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; ADC_InitStructure.ADC_NbrOfChannel = 4; ADC_Init(ADC1, &ADC_InitStructure); /* ADC1 regular channel 00 configuration */ ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_55Cycles5); /* ADC1 regular channel 01 configuration */ ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_55Cycles5); /* ADC1 regular channel 02 configuration */ ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 3, ADC_SampleTime_55Cycles5); /* ADC1 regular channel 03 configuration */ ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 4, ADC_SampleTime_55Cycles5); /* Enable ADC1 DMA */ ADC_DMACmd(ADC1, ENABLE); /* Enable ADC1 */ ADC_Cmd(ADC1, ENABLE); /* Enable ADC1 reset calibration register */ ADC_ResetCalibration(ADC1); /* Check the end of ADC1 reset calibration register */ while(ADC_GetResetCalibrationStatus(ADC1)); /* Start ADC1 calibration */ ADC_StartCalibration(ADC1); /* Check the end of ADC1 calibration */ while(ADC_GetCalibrationStatus(ADC1)); /* Start ADC1 Software Conversion */ ADC_SoftwareStartConvCmd(ADC1, ENABLE);}So far in my attempts when I add an additional A/D, all of my conversions that used to work stop working.init main(void){ ......// if(CAN message = 11, GPIOB Pin 0 conf. as an General Purpose I/O) case 11: /* Configure PB0 Out On */ GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOB, &GPIO_InitStructure); GPIO_WriteBit(GPIOB,GPIO_Pin_0,Bit_SET); CAN_AppTX.data[0] = 0x01;break;//if(CAN message = 12, GPIOB Pin 0 configured as an analog Input) case 12: /* Configure PB0 A/D */ GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; GPIO_Init(GPIOB, &GPIO_InitStructure); ADC_InitStructure.ADC_NbrOfChannel = 5; ADC_Init(ADC1, &ADC_InitStructure); ADC_RegularChannelConfig(ADC1, ADC_Channel_8, 5, ADC_SampleTime_55Cycles5); ADC_Cmd(ADC1, ENABLE); ADC_SoftwareStartConvCmd(ADC1, ENABLE); DMA_InitStructure.DMA_BufferSize = 5; DMA_Init(DMA1_Channel1, &DMA_InitStructure); DMA_Cmd(DMA1_Channel1, ENABLE);........}Thank you for any help. #stm32-adc