dac.c

/*
 * dac.c - interfacing the on-board STM32F4 DAC for noise generation
 *
 * Author: Dan Green (danngreen1@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.
 *
 * -----------------------------------------------------------------------------
 */

#include <stm32f4xx.h>
#include "dac.h"
#include "dig_inouts.h"
#include "globals.h"



DAC_InitTypeDef dac;

void DAC_Ch1_NoiseConfig(void)
{
	GPIO_InitTypeDef gpio;

	/* GPIOA clock enable (to be used with DAC) */
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
	/* DAC Periph clock enable */
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);


	gpio.GPIO_Pin = GPIO_Pin_4;
	gpio.GPIO_Mode = GPIO_Mode_AN;
	gpio.GPIO_PuPd = GPIO_PuPd_NOPULL;
	GPIO_Init(GPIOA, &gpio);

	dac.DAC_Trigger = DAC_Trigger_T6_TRGO;
	dac.DAC_WaveGeneration = DAC_WaveGeneration_Noise;
	dac.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bits11_0;
	dac.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
	DAC_Init(DAC_Channel_1, &dac);

	DAC_Cmd(DAC_Channel_1, ENABLE);

	DAC_SetChannel1Data(DAC_Align_12b_R, 0);

}

void update_TIM6(uint32_t period){
	TIM6->ARR = period;

}


void TIM6_Config(void)
{
  TIM_TimeBaseInitTypeDef    TIM_TimeBaseStructure;

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM6, ENABLE);

  /* Time base configuration */
  TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
  TIM_TimeBaseStructure.TIM_Period = 0x4000;
  TIM_TimeBaseStructure.TIM_Prescaler = 0;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInit(TIM6, &TIM_TimeBaseStructure);

  /* TIM6 TRGO selection */
  TIM_SelectOutputTrigger(TIM6, TIM_TRGOSource_Update);

  /* TIM6 enable counter */
  TIM_Cmd(TIM6, ENABLE);
}