text: // Copyright 2016 Emilie Gillet.
  //
  // Author: Emilie Gillet (emilie.o.gillet@gmail.com)
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  // 
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  // 
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  // THE SOFTWARE.
  // 
  // See http://creativecommons.org/licenses/MIT/ for more information.
  //
  // -----------------------------------------------------------------------------
  //
  // Drivers for the 12-bit ADC used for firmware updates through the MODEL CV in.
  
  #include "plaits/drivers/firmware_update_adc.h"
  
  #include <stm32f37x_conf.h>
  
  namespace plaits {
  
  void FirmwareUpdateAdc::Init() {
    // Enable ADC clock.
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
    RCC_ADCCLKConfig(RCC_PCLK2_Div8);
    
    // Enable GPIO clock.
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE);
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
    
    // Enable DMA1 clock.
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
    
    DMA_InitTypeDef dma_init;
    ADC_InitTypeDef adc_init;
    GPIO_InitTypeDef gpio_init;
    
    // Configure the two analog inputs.
    gpio_init.GPIO_Pin = GPIO_Pin_1;
    gpio_init.GPIO_PuPd = GPIO_PuPd_NOPULL;
    gpio_init.GPIO_OType = GPIO_OType_PP;
    gpio_init.GPIO_Mode = GPIO_Mode_AN;
    GPIO_Init(GPIOB, &gpio_init);
    
    gpio_init.GPIO_Pin = GPIO_Pin_0;
    GPIO_Init(GPIOA, &gpio_init);
    
    // Use DMA to automatically copy ADC data register to values_ buffer.
    dma_init.DMA_PeripheralBaseAddr = (uint32_t)&ADC1->DR;
    dma_init.DMA_MemoryBaseAddr = (uint32_t)&values_[0];
    dma_init.DMA_DIR = DMA_DIR_PeripheralSRC;
    dma_init.DMA_BufferSize = 2;
    dma_init.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    dma_init.DMA_MemoryInc = DMA_MemoryInc_Enable;
    dma_init.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
    dma_init.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
    dma_init.DMA_Mode = DMA_Mode_Circular;
    dma_init.DMA_Priority = DMA_Priority_High;
    dma_init.DMA_M2M = DMA_M2M_Disable;
    DMA_Init(DMA1_Channel1, &dma_init);
    DMA_Cmd(DMA1_Channel1, ENABLE);
  
    // Init ADC1.
    adc_init.ADC_ScanConvMode = ENABLE;
    adc_init.ADC_ContinuousConvMode = DISABLE;
    adc_init.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
    adc_init.ADC_DataAlign = ADC_DataAlign_Left;
    adc_init.ADC_NbrOfChannel = 2;
    ADC_Init(ADC1, &adc_init);
    
    // Sample rate: 53.6 kHz
    // 72000 / 6 / (12.5 * 2 + 71.5 * 2)
    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_71Cycles5);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_9, 2, ADC_SampleTime_71Cycles5);
    
    // Enable and calibrate ADC1.
    ADC_Cmd(ADC1, ENABLE);
    ADC_ResetCalibration(ADC1);
    while (ADC_GetResetCalibrationStatus(ADC1));
    ADC_StartCalibration(ADC1);
    while (ADC_GetCalibrationStatus(ADC1));
    ADC_DMACmd(ADC1, ENABLE);
  
    values_[0] = values_[1] = 32768;
    Convert();
  }
  
  void FirmwareUpdateAdc::DeInit() {
    ADC_DMACmd(ADC1, DISABLE);
    ADC_Cmd(ADC1, DISABLE);
    DMA_Cmd(DMA1_Channel1, DISABLE);
  }
  
  void FirmwareUpdateAdc::Convert() {
    ADC_SoftwareStartConv(ADC1);
  }
  
  }  // namespace plaits
  