stm8l15x_dac.c

STM8L的tim4定时器使用

/**
  ******************************************************************************
  * @file    stm8l15x_dac.c
  * @author  MCD Application Team
  * @version V1.5.0
  * @date    13-May-2011
  * @brief   This file provides firmware functions to manage the following 
  *          functionalities of the Digital-to-Analog Converter (DAC) peripheral: 
  *           - DAC channels configuration: trigger, output buffer, data format
  *           - DMA management      
  *           - Interrupts and flags management
  *
  *  @verbatim
  *    
  *          ===================================================================
  *                             DAC Peripheral features
  *          ===================================================================
  *          The device integrates two 12-bit Digital Analog Converters that can 
  *          be used independently or simultaneously (dual mode):
  *            1- DAC channel1 with DAC_OUT1 (PF0) as output
  *            1- DAC channel2 with DAC_OUT2 (PF1) as output
  *
  *          Digital to Analog conversion can be non-triggered using DAC_Trigger_None
  *          and DAC_OUT1/DAC_OUT2 is available once writing to DHRx register using 
  *          DAC_SetChannel1Data()/DAC_SetChannel2Data.
  *   
  *         Digital to Analog conversion can be triggered by:
  *             1- External event: PE4 using DAC_Trigger_Ext.
  *                This pin (PE4) must be configured in input mode.
  *
  *             2- Timers TRGO: TIM4, TIM5 
  *                (DAC_Trigger_T4_TRGO, DAC_Trigger_T5_TRGO)
  *                The timer TRGO event should be selected using TIMx_SelectOutputTrigger()
  *
  *             3- Software using DAC_Trigger_Software
  *
  *          Each DAC channel integrates an output buffer that can be used to 
  *          reduce the output impedance, and to drive external loads directly
  *          without having to add an external operational amplifier.
  *          
  *          Refer to the device datasheet for more details about output impedance
  *          value with and without output buffer.
  *
  *          Both DAC channels can be used to generate
  *             1- Noise wave using DAC_Wave_Noise
  *             2- Triangle wave using DAC_Wave_Triangle
  *        
  *
  *          The DAC data format can be:
  *             1- 8-bit right alignment using DAC_Align_8b_R
  *             2- 12-bit left alignment using DAC_Align_12b_L
  *             3- 12-bit right alignment using DAC_Align_12b_R
  *
  *          The analog output voltage on each DAC channel pin is determined
  *          by the following equation: DAC_OUTx = VREF+ * DOR / 4095
  *             with  DOR is the Data Output Register
  *                   VEF+ is the input voltage reference (refer to the device datasheet)
  *          e.g. To set DAC_OUT1 to 0.7V, use
  *            DAC_SetChannel1Data(DAC_Align_12b_R, 868);
  *          Assuming that VREF+ = 3.3, DAC_OUT1 = (3.3 * 868) / 4095 = 0.7V
  *
  *          A DMA1 request can be generated when an external trigger (but not
  *          a software trigger) occurs if DMA1 requests are enabled using
  *          DAC_DMACmd()
  *          DMA1 requests are mapped as following:
  *             1- DAC channel1 is mapped on DMA1 channel3 which must be already 
  *                configured
  *             2- DAC channel2 is mapped on DMA1 channel1 which must be already 
  *                configured
  *
  *          ===================================================================      
  *                              How to use this driver 
  *          ===================================================================          
  *            - DAC clock must be enabled to get write access to DAC registers using
  *              CLK_PeripheralClockConfig(CLK_Peripheral_DAC, ENABLE)
  *            - Configure DAC_OUTx (DAC_OUT1: PF0, DAC_OUT2: PF1) in analog mode.
  *            - Configure the DAC channel using DAC_Init()
  *            - Enable the DAC channel using DAC_Cmd()
  * 
  *  @endverbatim
  *    
  ******************************************************************************
  * @attention
  *
  * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  *
  * <h2><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h2>
  ******************************************************************************  
  */

/* Includes ------------------------------------------------------------------*/
#include "stm8l15x_dac.h"

/** @addtogroup STM8L15x_StdPeriph_Driver
  * @{
  */

/** @defgroup DAC 
  * @brief DAC driver modules
  * @{
  */ 
  
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/** @defgroup DAC_Private_Functions
  * @{
  */ 

/** @defgroup DAC_Group1 DAC channels configuration
 *  @brief   DAC channels configuration: trigger, output buffer, data format 
 *
@verbatim   
 ===============================================================================
          DAC channels configuration: trigger, output buffer, data format
 ===============================================================================  

@endverbatim
  * @{
  */

/**
  * @brief  Deinitializes the DAC peripheral registers to their default reset values.
  * @param  None
  * @retval None
  */
void DAC_DeInit(void)
{
  /*  Set Channel1  the Configuration registers to their reset values */
  DAC->CH1CR1 = DAC_CR1_RESET_VALUE;
  DAC->CH1CR2 = DAC_CR2_RESET_VALUE;

  /*  Set Channel2  the Configuration registers to their reset values */
  DAC->CH2CR1 = DAC_CR1_RESET_VALUE;
  DAC->CH2CR2 = DAC_CR2_RESET_VALUE;

  /*  Set the Software Trigger configuration registers to their reset values */
  DAC->SWTRIGR = DAC_SWTRIGR_RESET_VALUE;

  /*  Set the Status registers to their reset values */
  DAC->SR = (uint8_t)~DAC_SR_RESET_VALUE;

  /*  Set the Channel1 Data holding registers to their reset values */
  DAC->CH1RDHRH = DAC_RDHRH_RESET_VALUE;
  DAC->CH1RDHRL = DAC_RDHRL_RESET_VALUE;
  DAC->CH1LDHRH = DAC_LDHRH_RESET_VALUE;
  DAC->CH1LDHRL = DAC_LDHRL_RESET_VALUE;
  DAC->CH1DHR8 = DAC_DHR8_RESET_VALUE;

  /*  Set the Channel2 Data holding registers to their reset values */
  DAC->CH2RDHRH = DAC_RDHRH_RESET_VALUE;
  DAC->CH2RDHRL = DAC_RDHRL_RESET_VALUE;
  DAC->CH2LDHRH = DAC_LDHRH_RESET_VALUE;
  DAC->CH2LDHRL = DAC_LDHRL_RESET_VALUE;
  DAC->CH2DHR8 = DAC_DHR8_RESET_VALUE;

  /*  Set the Dual mode 12bit Right Data holding registers to their reset values */
  DAC->DCH1RDHRH = DAC_RDHRH_RESET_VALUE;
  DAC->DCH1RDHRL = DAC_RDHRL_RESET_VALUE;
  DAC->DCH2RDHRH = DAC_RDHRH_RESET_VALUE;
  DAC->DCH2RDHRL = DAC_RDHRL_RESET_VALUE;

  /*  Set the Dual mode 12bit Left Data holding registers to their reset values */
  DAC->DCH1LDHRH = DAC_LDHRH_RESET_VALUE;
  DAC->DCH1LDHRL = DAC_LDHRL_RESET_VALUE;
  DAC->DCH2LDHRH = DAC_LDHRH_RESET_VALUE;
  DAC->DCH2LDHRL = DAC_LDHRL_RESET_VALUE;

  /*  Set the Dual mode 8bit Data holding registers to their reset values */
  DAC->DCH1DHR8 = DAC_DHR8_RESET_VALUE;
  DAC->DCH2DHR8 = DAC_DHR8_RESET_VALUE;
}

/**
  * @brief  Initializes the DAC according to the specified parameters.
  * @param  DAC_Channel: the selected DAC channel. 
  *          This parameter can be one of the following values:
  *            @arg DAC_Channel_1: DAC Channel1 selected
  *            @arg DAC_Channel_2: DAC Channel2 selected
  * @param  DAC_Trigger : the selected DAC trigger. 
  *          This parameter can be one of the following values:
  *            @arg DAC_Trigger_None: DAC trigger None 
  *            @arg DAC_Trigger_T4_TRGO: DAC trigger TIM4 TRGO
  *            @arg DAC_Trigger_T5_TRGO: DAC trigger TIM5 TRGO
  *            @arg DAC_Trigger_Ext: DAC trigger External Trigger (PE4)  
  *            @arg DAC_Trigger_Software: DAC trigger software 
  * @param  DAC_OutputBuffer : the status of DAC load Buffer
  *          This parameter can be one of the following values:
  *            @arg DAC_OutputBuffer_Enable: DAC output buffer Enabled
  *            @arg DAC_OutputBuffer_Disable: DAC output buffer Disabled  
  * @retval None
  */
void DAC_Init(DAC_Channel_TypeDef DAC_Channel,
              DAC_Trigger_TypeDef DAC_Trigger,
              DAC_OutputBuffer_TypeDef DAC_OutputBuffer)
{
  uint8_t tmpreg = 0;
  uint16_t tmpreg2 = 0;

  /* Check the DAC parameters */
  assert_param(IS_DAC_CHANNEL(DAC_Channel));
  assert_param(IS_DAC_TRIGGER(DAC_Trigger));
  assert_param(IS_DAC_OUTPUT_BUFFER_STATE(DAC_OutputBuffer));

  /* Get the DAC CHxCR1 value */
  tmpreg2 =  (uint16_t)((uint8_t)((uint8_t)DAC_Channel << 1));
  tmpreg = *(uint8_t*)((uint16_t)(DAC_BASE + CR1_Offset + tmpreg2));

  /* Clear BOFFx, TENx, TSELx bits */
  tmpreg &= (uint8_t)~(DAC_CR1_BOFF | DAC_CR1_TEN | DAC_CR1_TSEL );

  /* Set BOFFx bit according to DAC_OutputBuffer value */
  tmpreg |= (uint8_t)(DAC_OutputBuffer);


  /* Configure for the selected DAC channel trigger*/
  if (DAC_Trigger != DAC_Trigger_None)
  {
    /* Set TSELx and TEN  bits according to DAC_Trigger value */
    tmpreg |= (uint8_t)(DAC_CR1_TEN | DAC_Trigger) ;
  }

  /* Write to DAC CHxCR1 */
  *(uint8_t*)((uint16_t)(DAC_BASE + CR1_Offset + tmpreg2)) = (uint8_t)tmpreg;
}

/**
  * @brief  Enables or disables the specified DAC channel.
  * @param  DAC_Channel: the selected DAC channel. 
  *          This parameter can be one of the following values:
  *            @arg DAC_Channel_1: DAC Channel1 selected
  *            @arg DAC_Channel_2: DAC Channel2 selected
  * @param  NewState: new state of the DAC channel. 
  *      This parameter can be: ENABLE or DISABLE.
  * @note When the DAC channel is enabled the trigger source can no more
  *       be modified.
  * @retval None
  */
void DAC_Cmd(DAC_Channel_TypeDef DAC_Channel, FunctionalState NewState)
{
  uint16_t cr1addr = 0;
  /* Check the parameters */
  assert_param(IS_DAC_CHANNEL(DAC_Channel));
  assert_param(IS_FUNCTIONAL_STATE(NewState));

  /* Find CHxCR1 register Address */
  cr1addr = DAC_BASE + CR1_Offset + (uint8_t)((uint8_t)DAC_Channel << 1);

  if (NewState != DISABLE)
  {
    /* Enable the selected DAC channel */
    (*(uint8_t*)(cr1addr)) |= DAC_CR1_EN;
  }
  else
  {
    /* Disable the selected DAC channel */
    (*(uint8_t*)(cr1addr)) &= (uint8_t) ~(DAC_CR1_EN);
  }
}

/**
  * @brief  Enables or disables the selected DAC channel software trigger.
  * @param  DAC_Channel: the selected DAC channel. 
  *          This parameter can be one of the following values:
  *            @arg DAC_Channel_1: DAC Channel1 selected
  *            @arg DAC_Channel_2: DAC Channel2 selected
  * @param  NewState: new state of the selected DAC channel software trigger.
  *          This parameter can be: ENABLE or DISABLE.
  * @retval None.