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drivers: added LPS331AP pressure sensor driver

dev/timer
Hauke Petersen 8 years ago committed by Hauke Petersen
parent
commit
7b666eb2a9
  1. 3
      drivers/Makefile
  2. 3
      drivers/Makefile.include
  3. 112
      drivers/include/lps331ap.h
  4. 3
      drivers/lps331ap/Makefile
  5. 70
      drivers/lps331ap/include/lps331ap-internal.h
  6. 131
      drivers/lps331ap/lps331ap.c

3
drivers/Makefile

@ -49,5 +49,8 @@ endif
ifneq (,$(filter mq3,$(USEMODULE)))
DIRS += mq3
endif
ifneq (,$(filter lps331ap,$(USEMODULE)))
DIRS += lps331ap
endif
include $(RIOTBASE)/Makefile.base

3
drivers/Makefile.include

@ -13,3 +13,6 @@ endif
ifneq (,$(filter isl29020,$(USEMODULE)))
USEMODULE_INCLUDES += $(RIOTBASE)/drivers/isl29020/include
endif
ifneq (,$(filter lps331ap,$(USEMODULE)))
USEMODULE_INCLUDES += $(RIOTBASE)/drivers/lps331ap/include
endif

112
drivers/include/lps331ap.h

@ -0,0 +1,112 @@
/*
* Copyright (C) 2014 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.
*/
/**
* @defgroup driver_lps331ap LPS331AP Pressure Sensor Driver
* @ingroup drivers
* @brief Device driver for the LPS331AP pressure sensor
* @{
*
* @file
* @brief Device driver interface for the LPS331AP pressure sensor
*
* @note This driver uses the sensors I2C interface
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*/
#ifndef __LPS331AP_H
#define __LPS331AP_H
#ifdef __cplusplus
extern "C" {
#endif
#include <stdint.h>
#include "periph/i2c.h"
/**
* @name The sensors default I2C address
*/
#define LPS331AP_DEFAULT_ADDRESS 0x5c
/**
* @brief Device descriptor for LPS331AP sensors
*/
typedef struct {
i2c_t i2c; /**< I2C device the sensor is connected to */
uint8_t address; /**< I2C bus address of the sensor */
} lps331ap_t;
/**
* @brief Possible sampling rates for LPS331AP sensors
*/
typedef enum {
LPS331AP_RATE_1HZ = 1, /**< sample with 1Hz */
LPS331AP_RATE_7HZ = 5, /**< sample with 7Hz */
LPS331AP_RATE_12HZ5 = 6, /**< sample with 12.5Hz */
LPS331AP_RATE_25HZ = 7 /**< sample with 25Hz */
} lps331ap_rate_t;
/**
* @brief Initialize a given LPS331AP pressure sensor
*
* @param[out] dev device descriptor of the sensor
* @param[in] i2c I2C bus the sensor is connected to
* @param[in] address the sensor's address on the I2C bus
* @param[in] rate internal sampling rate of the sensor
*
* @return 0 on success
* @return -1 on error
*/
int lps331ap_init(lps331ap_t *dev, i2c_t i2c, uint8_t address, lps331ap_rate_t rate);
/**
* @brief Read a temperature value from the given sensor, returned in m°C
*
* @param[in] dev device descriptor of sensor to read from
*
* @return temperature value in m°C
*/
int lps331ap_read_temp(lps331ap_t *dev);
/**
* @brief Read a pressure value from the given sensor, returned in mbar
*
* @param[in] dev device descriptor of sensor to read from
*
* @return pressure value in mbar
*/
int lps331ap_read_pres(lps331ap_t *dev);
/**
* @brief Enable the given sensor
*
* @param[in] dev device descriptor of sensor to enable
*
* @return 0 on success
* @return -1 on error
*/
int lps331ap_enable(lps331ap_t *dev);
/**
* @brief Disable the given sensor
*
* @param[in] dev device descriptor of sensor to disable
*
* @return 0 on success
* @return -1 on error
*/
int lps331ap_disable(lps331ap_t *dev);
#ifdef __cplusplus
}
#endif
#endif /* __LPS331AP_H */
/** @} */

3
drivers/lps331ap/Makefile

@ -0,0 +1,3 @@
MODULE = lps331ap
include $(RIOTBASE)/Makefile.base

70
drivers/lps331ap/include/lps331ap-internal.h

@ -0,0 +1,70 @@
/*
* Copyright (C) 2014 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.
*/
/**
* @ingroup driver_lps331ap
* @{
*
* @file
* @brief Definitions for the LPS331AP pressure sensor
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*/
#ifndef __LPS331AP_INTERNAL_H
#define __LPS331AP_INTERNAL_H
#ifdef __cplusplus
extern "C" {
#endif
/**
* @name LPS331AP registers
* @{
*/
#define LPS331AP_AUTO_INC 0x80
#define LPS331AP_REG_REF_P_XL 0x08
#define LPS331AP_REG_REF_P_L 0x09
#define LPS331AP_REG_REF_P_H 0x0a
#define LPS331AP_REG_WHO_AM_I 0x0f
#define LPS331AP_REG_RES_CONF 0x10
#define LPS331AP_REG_CTRL_REG1 0x20
#define LPS331AP_REG_CTRL_REG2 0x21
#define LPS331AP_REG_CTRL_REG3 0x22
#define LPS331AP_REG_INT_CFG_REG 0x23
#define LPS331AP_REG_INT_SOURCE_REG 0x24
#define LPS331AP_REG_THS_P_LOW_REG 0x25
#define LPS331AP_REG_THS_P_HIGH_REG 0x26
#define LPS331AP_REG_STATUS_REG 0x27
#define LPS331AP_REG_PRESS_OUT_XL 0x28
#define LPS331AP_REG_PRESS_OUT_L 0x29
#define LPS331AP_REG_PRESS_OUT_H 0x2a
#define LPS331AP_REG_TEMP_OUT_L 0x2b
#define LPS331AP_REG_TEMP_OUT_H 0x2c
#define LPS331AP_REG_AMP_CTRL 0x30
/** @} */
/**
* @name LPS331AP CTRL_REG1 bitfields
* @{
*/
#define LPS331AP_CTRL_REG1_PD 0x80
#define LPS331AP_CTRL_REG1_ODR 0x70
#define LPS331AP_CTRL_REG1_ODR_POS 4
#define LPS331AP_CTRL_REG1_DIFF_EN 0x08
#define LPS331AP_CTRL_REG1_DBDU 0x04
#define LPS331AP_CTRL_REG1_DELTA_EN 0x02
#define LPS331AP_CTRL_REG1_SIM 0x01
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* __LPS331AP_INTERNAL_H */
/** @} */

131
drivers/lps331ap/lps331ap.c

@ -0,0 +1,131 @@
/*
* Copyright (C) 2014 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.
*/
/**
* @ingroup driver_lps331ap
* @{
*
* @file
* @brief Device driver implementation for the LPS331AP pressure sensor
*
* @note The current driver implementation is very basic and allows only for polling the
* devices temperature and pressure values. Threshold values and interrupts are not
* used.
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*
* @}
*/
#include <stdint.h>
#include "periph/i2c.h"
#include "lps331ap.h"
#include "lps331ap-internal.h"
/**
* @brief default I2C bus speed for this sensor
*/
#define BUS_SPEED I2C_SPEED_FAST
/**
* @brief pressure divider for norming pressure output
*/
#define PRES_DIVIDER (4096U)
/**
* @brief temperature base value and divider for norming temperature output
*/
#define TEMP_BASE (42.5f)
#define TEMP_DIVIDER (480U)
int lps331ap_init(lps331ap_t *dev, i2c_t i2c, uint8_t address, lps331ap_rate_t rate)
{
char tmp;
/* save device specifics */
dev->i2c = i2c;
dev->address = address;
/* initialize underlying I2C bus */
if (i2c_init_master(dev->i2c, BUS_SPEED) < 0) {
return -1;
}
/* configure device, for simple operation only CTRL_REG1 needs to be touched */
tmp = LPS331AP_CTRL_REG1_DBDU | LPS331AP_CTRL_REG1_PD |
(rate << LPS331AP_CTRL_REG1_ODR_POS);
if (i2c_write_reg(dev->i2c, dev->address, LPS331AP_REG_CTRL_REG1, tmp) != 1) {
return -1;
}
return 0;
}
int lps331ap_read_temp(lps331ap_t *dev)
{
char tmp;
int16_t val = 0;
float res = TEMP_BASE; /* reference value -> see datasheet */
i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_TEMP_OUT_L, &tmp);
val |= tmp;
i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_TEMP_OUT_H, &tmp);
val |= (tmp << 8);
/* compute actual temperature value in °C */
res += ((float)val) / TEMP_DIVIDER;
/* return temperature in m°C */
return (int)(res * 1000);
}
int lps331ap_read_pres(lps331ap_t *dev)
{
char tmp;
int32_t val = 0;
float res;
i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_PRESS_OUT_XL, &tmp);
val |= tmp;
i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_PRESS_OUT_L, &tmp);
val |= (tmp << 8);
i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_PRESS_OUT_H, &tmp);
val |= (tmp << 16);
/* see if value is negative */
if (tmp & 0x80) {
val |= (0xff << 24);
}
/* compute actual pressure value in mbar */
res = ((float)val) / PRES_DIVIDER;
return (int)res;
}
int lps331ap_enable(lps331ap_t *dev)
{
char tmp;
if (i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_CTRL_REG1, &tmp) != 1) {
return -1;
}
tmp |= (LPS331AP_CTRL_REG1_PD);
return i2c_write_reg(dev->i2c, dev->address, LPS331AP_REG_CTRL_REG1, tmp);
}
int lps331ap_disable(lps331ap_t *dev)
{
char tmp;
if (i2c_read_reg(dev->i2c, dev->address, LPS331AP_REG_CTRL_REG1, &tmp) != 1) {
return -1;
}
tmp &= ~(LPS331AP_CTRL_REG1_PD);
return i2c_write_reg(dev->i2c, dev->address, LPS331AP_REG_CTRL_REG1, tmp);
}
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