Browse Source

drivers/dac: reworked DAC driver interface

pr/gpio
Hauke Petersen 7 years ago
parent
commit
40ae604c3b
  1. 155
      drivers/include/periph/dac.h

155
drivers/include/periph/dac.h

@ -1,5 +1,6 @@
/*
* Copyright (C) 2014 Simon Brummer
* 2015-2016 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
@ -9,144 +10,116 @@
/**
* @defgroup drivers_periph_dac DAC
* @ingroup drivers_periph
* @brief Low-level DAC peripheral driver
* @brief DAC peripheral driver interface
*
* Similar to the ADC driver interface (@ref drivers_periph_adc), the DAC
* interface uses the concept of lines, corresponds to a tuple of a DAC device
* and a DAC output channel.
*
* The DAC interface expects data to be served as a 16-bit unsigned integer,
* independent of the actual resolution of the hardware device. It is up to the
* DAC driver, to scale the given value to the maximal width that can be
* handled. The device driver should, on the other hand, implement the DAC in a
* way, that it will use the bit width, that comes closest to 16-bit.
*
* This kind of 'auto-scaling' is quite sufficient for this interface, as
* standard DAC peripherals use a fixed conversion resolution internally anyway,
* so that any particular bit-width configuration on this driver level would not
* have much effect...
*
* @{
* @file
* @brief Low-level DAC peripheral driver interface definitions
* @brief DAC peripheral driver interface definition
*
* @author Simon Brummer <simon.brummer@haw-hamburg.de>
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*/
#ifndef DAC_H
#define DAC_H
#ifndef PERIPH_DAC_H
#define PERIPH_DAC_H
#include <stdint.h>
#include <limits.h>
#include "periph_cpu.h"
#include "periph_conf.h"
#ifdef __cplusplus
extern "C" {
#endif
/* guard file in case no DAC device is defined */
#if DAC_NUMOF
/**
* @brief Definition avialable DAC devices
*
* Each DAC device is based on a hardware DAC which can have one or more
* independet channels.
* @brief Make sure the number of available DAC lines is defined
* @{
*/
typedef enum {
#if DAC_0_EN
DAC_0 = 0, /**< DAC device 0 */
#endif
#if DAC_1_EN
DAC_1 = 1, /**< DAC device 1 */
#endif
#if DAC_2_EN
DAC_2 = 2, /**< DAC device 2 */
#endif
#if DAC_3_EN
DAC_3 = 3, /**< DAC device 3 */
#ifndef DAC_NUMOF
#define "DAC_NUMOF undefined"
#endif
} dac_t;
/** @} */
/**
* @brief Possilbe DAC precision settings
* @brief Define default DAC type identifier
* @{
*/
typedef enum {
DAC_RES_6BIT = 0, /**< DAC precision: 6 bit */
DAC_RES_8BIT, /**< DAC precision: 8 bit */
DAC_RES_10BIT, /**< DAC precision: 10 bit */
DAC_RES_12BIT, /**< DAC precision: 12 bit */
DAC_RES_14BIT, /**< DAC precision: 14 bit */
DAC_RES_16BIT, /**< DAC precision: 16 bit */
} dac_precision_t;
#ifndef HAVE_DAC_T
typedef unsigned int dac_t;
#endif
/** @} */
/**
* @brief Initialization of a given DAC device
*
* The DAC will be initialized with all possilble channels active.
* On each channel will be initialized with a Zero on it.
*
* @param[in] dev the device to initialize
* @param[in] precision the precision to use for conversion
*
* @return 0 on success
* @return -1 on unknown DAC Device
* @return -2 on precision not available
* @brief Default DAC undefined value
* @{
*/
int8_t dac_init(dac_t dev, dac_precision_t precision);
#ifndef DAC_UNDEF
#define DAC_UNDEF (UINT_MAX)
#endif
/** @} */
/**
* @brief Write a value onto DAC Device on a given Channel.
*
* @param[in] dev the DAC device to use
* @param[in] channel the channel used for Digital/Analoge conversion
* @param[in] value the value to write onto DAC.
*
* @return 0 on success
* @return -1 on unknown DAC Device
* @return -2 on invalid channel
* @return -3 if value is out of range.
* @brief Default DAC access macro
* @{
*/
int8_t dac_write(dac_t dev, uint8_t channel, uint16_t value);
#ifndef DAC_LINE
#define DAC_LINE(x) (x)
#endif
/** @} */
/**
* @brief Enable power for the given DAC Device
* @brief Initialize the given DAC line
*
* @param[in] dev the DAC device to power up.
* @param[in] line DAC line to initialize
*
* @return 0 on success
* @return -1 on unknown DAC Device
* @return -1 on invalid DAC line
*/
int8_t dac_poweron(dac_t dev);
int8_t dac_init(dac_t line);
/**
* @brief Disable power for the given DAC Device
*
* @param[in] dev the DAC device to power down
* @brief Write a value onto DAC Device on a given Channel.
*
* @return 0 on success
* @return -1 on unknown DAC Device
* @param[in] line DAC line to set
* @param[in] value value to set @p line to
*/
int8_t dac_poweroff(dac_t dev);
void dac_set(dac_t line, uint16_t value);
/**
* @brief Helper function to map a given integer range to a valid DAC value.
*
* This function is useful for converting ranges of values to a valid DAC output value.
*
* The min value is assumed to be smaller than max value and value is assumed
* to be between min and max.
*
* @param[in] dev the DAC Device to read precision value from
* @param[in] value the value to map onto min and max
* @param[in] min the lower bound of the target interval
* @param[in] max the upper bound of the target interval
* @brief Enable the given DAC line
*
* @return the mapped value, in valid DAC range
* @param[in] line DAC line to power on
*/
uint16_t dac_map(dac_t dev, int value, int min, int max);
void dac_poweron(dac_t line);
/**
* @brief Helper function to map a given float value range to a valid DAC value.
* @brief Disable the given DAC line
*
* @see dac_map
*
* @param[in] dev the DAC Device to read precision value from
* @param[in] value the value to map onto min and max
* @param[in] min the lower bound of the target interval
* @param[in] max the upper bound of the target interval
*
* @return the mapped value, in valid DAC range
* @param[in] line DAC line to power off
*/
uint16_t dac_mapf(dac_t dev, float value, float min, float max);
void dac_poweroff(dac_t line);
#endif/* DAC_NUMOF */
#ifdef __cplusplus
}
#endif
#endif /* DAC_H */
#endif /* PERIPH_DAC_H */
/** @} */

Loading…
Cancel
Save