kaspar/RIOT
1
0
Fork 0
mirror of https://github.com/RIOT-OS/RIOT.git synced 2025-12-25 06:23:53 +01:00
Code Releases Activity

cpu/stm32f4: reworked DAC driver implementation

Browse Source
This commit is contained in:
Hauke Petersen 2016-03-14 20:10:58 +01:00
parent 74bd800903
commit ea63bf454c
2 changed files with 48 additions and 128 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
cpu/stm32f4/include/periph_cpu.h
View File

@ -137,6 +137,14 @@ typedef struct {
uint8_t chan; /**< CPU ADC channel connected to the pin */
} adc_conf_t;
/**
* @brief DAC line configuration data
*/
typedef struct {
gpio_t pin; /**< pin connected to the line */
uint8_t chan; /**< DAC device used for this line */
} dac_conf_t;
/**
* @brief Configure the alternate function for the given pin
*

168
cpu/stm32f4/periph/dac.c
View File

@ -1,9 +1,10 @@
/*
* 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 directory for more
* details.
* 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
* directory for more details.
*/
/**
@ -13,7 +14,8 @@
* @file
* @brief Low-level DAC driver implementation
*
* @author Simon Brummer<simon.brummer@haw-hamburg.de>
* @author Simon Brummer <simon.brummer@haw-hamburg.de>
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*
* @}
*/
@ -22,145 +24,55 @@
#include "periph/dac.h"
#include "periph_conf.h"
/* guard in case that no DAC device is defined */
#if DAC_NUMOF
/* only compile this, if the CPU has a DAC */
#ifdef DAC
#define DAC_MAX_12BIT 0x0fff
typedef struct {
uint8_t shift_mod;
} dac_config_t;
dac_config_t dac_config[DAC_NUMOF];
int8_t dac_init(dac_t dev, dac_precision_t precision)
{
DAC_TypeDef *dac = 0;
dac_poweron(dev);
switch (dev) {
#if DAC_0_EN
case DAC_0:
dac = DAC_0_DEV;
DAC_0_PORT_CLKEN();
/* Set Mode to analoge out, disable Pullup Pulldown Resistors for both channels */
DAC_0_PORT->MODER |= (3 << (DAC_0_CH0_PIN * 2) | 3 << (DAC_0_CH1_PIN * 2));
DAC_0_PORT->PUPDR &= ~(3 << (DAC_0_CH0_PIN * 2) | 3 << (DAC_0_CH1_PIN * 2));
break;
/**
* @brief Get the DAC configuration from the board (if configured)
* @{
*/
#ifdef DAC_CONFIG
static const dac_conf_t dac_config[] = DAC_CONFIG;
#else
static const dac_conf_t dac_config[] = {};
#endif
default:
/* Unknown Device */
return -1;
/** @} */
int8_t dac_init(dac_t line)
{
if (line >= DAC_NUMOF) {
return -1;
}
/* Select Shift value to normalize given Value */
switch(precision) {
case DAC_RES_6BIT:
dac_config[dev].shift_mod = 0x06; /* 2^6 << 6 = 2^12 */
break;
case DAC_RES_8BIT:
dac_config[dev].shift_mod = 0x04; /* 2^8 << 4 = 2^12 */
break;
case DAC_RES_10BIT:
dac_config[dev].shift_mod = 0x02; /* 2^10 << 2 = 2^12 */
break;
case DAC_RES_12BIT:
dac_config[dev].shift_mod = 0x00; /* 2^12 << 0 = 2^12 */
break;
/* Not Supported Resolutions */
case DAC_RES_14BIT:
case DAC_RES_16BIT:
default:
dac_poweroff(dev);
return -2;
break;
}
/* Enable Channels, Clear Output */
dac->CR = 0;
dac->CR |= (DAC_CR_EN1 | DAC_CR_EN2);
dac->DHR12R1 = 0;
dac->DHR12R2 = 0;
/* configure pin */
gpio_init_analog(dac_config[line].pin);
/* enable the DAC's clock */
RCC->APB1ENR |= RCC_APB1ENR_DACEN;
/* reset output and enable the line's channel */
dac_set(line, 0);
dac_poweron(line);
return 0;
}
int8_t dac_write(dac_t dev, uint8_t channel, uint16_t value)
void dac_set(dac_t line, uint16_t value)
{
DAC_TypeDef* __attribute__((unused)) dac = 0;
uint16_t __attribute__((unused)) val = value << dac_config[dev].shift_mod;
switch(dev){
#if DAC_0_EN
case DAC_0:
dac = DAC_0_DEV;
if( DAC_MAX_12BIT < val ){
/* Value out of Range */
return -3;
}
switch(channel){
case 0:
dac->DHR12R1 = val;
break;
case 1:
dac->DHR12R2 = val;
break;
/* Invalid Channel */
default:
return -2;
}
break;
#endif
/* Unknown Device */
default:
return -1;
value = (value >> 4); /* scale to 12-bit */
if (dac_config[line].chan) {
DAC->DHR12R2 = value;
}
return 0;
}
int8_t dac_poweron(dac_t dev)
{
switch (dev){
#if DAC_0_EN
case DAC_0:
DAC_0_CLKEN();
break;
#endif
default:
/* Unknown Device */
return -1;
else {
DAC->DHR12R1 = value;
}
return 0;
}
int8_t dac_poweroff(dac_t dev)
void dac_poweron(dac_t line)
{
switch (dev) {
#if DAC_0_EN
case DAC_0:
DAC_0_CLKDIS();
break;
#endif
default:
/* Unknown Device */
return -1;
}
return 0;
DAC->CR |= (1 << (16 * dac_config[line].chan));
}
uint16_t dac_map(dac_t dev, int value, int min, int max)
void dac_poweroff(dac_t line)
{
return dac_mapf(dev, (int) value, (int) min, (int) max);
DAC->CR &= ~(1 << (16 * dac_config[line].chan));
}
uint16_t dac_mapf(dac_t dev, float value, float min, float max)
{
uint16_t val_12_bit = ((value - min) * DAC_MAX_12BIT)/(max-min);
return val_12_bit >> dac_config[dev].shift_mod;
}
#undef DAC_MAX_12BIT
#endif /* DAC_NUMOF */
#endif /* DAC */