add hdc1000 sensor driver

drivers/hdc1000/Makefile

@@ -0,0 +1 @@
+include $(RIOTBASE)/Makefile.base

drivers/hdc1000/hdc1000.c

@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2014 PHYTEC Messtechnik GmbH
+ *
+ * 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     drivers_hdc1000
+ * @{
+ *
+ * @file
+ * @brief       Driver for the TI HDC1000 Humidity and Temperature Sensor.
+ *
+ * @author      Johann Fischer <j.fischer@phytec.de>
+ *
+ * @}
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "periph/i2c.h"
+#include "hdc1000.h"
+
+#define ENABLE_DEBUG    (0)
+#include "debug.h"
+
+/**
+ * @brief Register Map
+ */
+#define HDC1000_TEMPERATURE        0x00
+#define HDC1000_HUMIDITY           0x01
+#define HDC1000_CONFG              0x02
+#define HDCD1000_SID1              0xFB
+#define HDCD1000_SID2              0xFC
+#define HDCD1000_SID3              0xFD
+#define HDC1000_MANUFACTURER_ID    0xFE
+#define HDC1000_DEVICE_ID          0xFF
+
+/**
+ * @brief Configuration Register Description
+ */
+#define HDC1000_CONFG_RST          (1 << 15)
+#define HDC1000_CONFG_HEAT         (1 << 13)
+#define HDC1000_CONFG_SEQ_MOD      (1 << 12)
+#define HDC1000_CONFG_BTST_LOW     (1 << 11)
+#define HDC1000_CONFG_TRES_MSK     (1 << 10)
+#define HDC1000_CONFG_TRES_11      (1 << 10)
+#define HDC1000_CONFG_TRES_14      0
+#define HDC1000_CONFG_HRES_MSK     (1 << 9 | 1 << 8)
+#define HDC1000_CONFG_HRES_14      0
+#define HDC1000_CONFG_HRES_11      (1 << 8)
+#define HDC1000_CONFG_HRES_8       (1 << 9)
+
+/**
+ * @brief Manufacturer and Device ID
+ */
+#define HDC1000_MID_VALUE          0x5449
+#define HDC1000_DID_VALUE          0x1000
+
+#define I2C_SPEED                  I2C_SPEED_FAST
+
+int hdc1000_test(hdc1000_t *dev)
+{
+    char reg[2];
+    uint16_t tmp;
+
+    if (i2c_read_regs(dev->i2c, dev->addr, HDC1000_MANUFACTURER_ID, reg, 2) != 2) {
+        return -1;
+    }
+    tmp = ((uint16_t)reg[0] << 8) | reg[1];
+    if (tmp != HDC1000_MID_VALUE) {
+        return -1;
+    }
+    
+    return 0;
+}
+
+int hdc1000_init(hdc1000_t *dev, i2c_t i2c, uint8_t address)
+{
+    char reg[2];
+
+    /* write device descriptor */
+    dev->i2c = i2c;
+    dev->addr = address;
+    dev->initialized = false;
+
+    /* initialize the I2C bus */
+    if (i2c_init_master(i2c, I2C_SPEED) < 0) {
+        return -1;
+    }
+
+    if (hdc1000_test(dev)) {
+        return -2;
+    }
+
+    /* set 14 bit resolution for both sensors and sequence mode */
+    uint16_t tmp = HDC1000_CONFG_SEQ_MOD;
+    reg[0] = (uint8_t)(tmp >> 8);
+    reg[1] = (uint8_t)tmp;
+
+    if (i2c_write_regs(dev->i2c, dev->addr, HDC1000_CONFG, reg, 2) != 2) {
+        return -3;
+    }
+    dev->initialized = true;
+
+    return 0;
+}
+
+int hdc1000_reset(hdc1000_t *dev)
+{
+    char reg[2];
+    uint16_t tmp = HDC1000_CONFG_RST;
+    reg[0] = (uint8_t)(tmp >> 8);
+    reg[1] = (uint8_t)tmp;
+    dev->initialized = false;
+
+    if (i2c_write_regs(dev->i2c, dev->addr, HDC1000_CONFG, reg, 2) != 2) {
+        return -1;
+    }
+    return 0;
+}
+
+int hdc1000_startmeasure(hdc1000_t *dev)
+{
+    if (dev->initialized == false) {
+        return -1;
+    }
+    /* Trigger the measurements by executing a write access
+     * to the address 0x00 (HDC1000_TEMPERATURE).
+     * Conversion Time is 6.50ms by 14 bit resolution.
+     */
+    if (i2c_write_bytes(dev->i2c, dev->addr, HDC1000_TEMPERATURE, 1) != 1) {
+        return -1;
+    }
+    return 0;
+}
+
+int hdc1000_read(hdc1000_t *dev, uint16_t *rawtemp, uint16_t *rawhum)
+{
+    char buf[4];
+
+    if (dev->initialized == false) {
+        return -1;
+    }
+    if (i2c_read_bytes(dev->i2c, dev->addr, buf, 4) != 4) {
+        return -1;
+    }
+    /* Register bytes are sent MSB first. */
+    *rawtemp = ((uint16_t)buf[0] << 8) | buf[1];
+    *rawhum = ((uint16_t)buf[2] << 8) | buf[3];
+  
+    return 0;
+}
+
+void hdc1000_convert(uint16_t rawtemp, uint16_t rawhum,  int *temp, int *hum)
+{
+    /* calculate temperature*100 [°C] */
+    *temp = (int)((((int32_t)rawtemp * 16500) >> 16) - 4000);
+    DEBUG("hdc1000 : T: %d\n", *temp);
+
+    /* calculate relative humidity*100 [%RH] */
+    *hum = (int)(((int32_t)rawhum * 10000) >> 16);
+    DEBUG("hdc1000 : RH: %d\n", *hum);
+}

drivers/include/hdc1000.h

@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2014 PHYTEC Messtechnik GmbH
+ *
+ * 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    drivers_hdc1000 HDC1000 Humidity and Temperature Sensor
+ * @ingroup     drivers
+ * @brief       Driver for the Texas Instruments HDC1000
+ *              Humidity and Temperature Sensor.
+ *              The driver will initialize the sensor for best
+ *              resolution (14 bit). Currently the driver doesn't use the heater.
+ *              Temperature and humidity are acquired in sequence.
+ *              The sensor is always in sleep mode. The measurement must
+ *              be started by a write access to the address 0x00
+ *              (HDC1000_TEMPERATURE). After completing the measurement
+ *              the sensor will return to sleep mode. Typical
+ *              Conversion Time by 14 bit resolution is 6.50ms.
+ *
+ * @{
+ *
+ * @file
+ * @brief       Interface definition for the HDC1000 sensor driver.
+ *
+ * @author      Johann Fischer <j.fischer@phytec.de>
+ */
+
+#ifndef HDC1000_H
+#define HDC1000_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "periph/i2c.h"
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+#ifndef HDC1000_I2C_ADDRESS
+#define HDC1000_I2C_ADDRESS           0x41
+#endif
+
+#ifndef HDC1000_CONVERSION_TIME
+#define HDC1000_CONVERSION_TIME       6500
+#endif
+
+/**
+ * @brief Device descriptor for HDC1000 sensors.
+ */
+typedef struct {
+    i2c_t i2c;              /**< I2C device the sensor is connected to */
+    uint8_t addr;           /**< the sensor's slave address on the I2C bus */
+    bool initialized;       /**< sensor status, true if sensor is initialized */
+} hdc1000_t;
+
+/**
+ * @brief HDC1000 sensor test.
+ * This function looks for Manufacturer ID of the HDC1000 sensor.
+ *
+ * @param[in]  dev          device descriptor of sensor
+ *
+ * @return                  0 on success
+ * @return                  -1 on error
+ */
+int hdc1000_test(hdc1000_t *dev);
+
+/**
+ * @brief Initialise the HDC1000 sensor driver.
+ * 14 bit resolution, heater off, temperature and humidity
+ * are acquired in sequence.
+ *
+ * @param[out] dev          device descriptor of sensor to initialize
+ * @param[in]  i2c          I2C bus the sensor is connected to
+ * @param[in]  address      sensor's I2C slave address
+ *
+ * @return                  0 on success
+ * @return                  -1 if initialization of I2C bus failed
+ * @return                  -2 if sensor test failed
+ * @return                  -3 if sensor configuration failed
+ */
+int hdc1000_init(hdc1000_t *dev, i2c_t i2c, uint8_t address);
+
+/**
+ * @brief Reset the HDC1000 sensor. After that sensor should be reinitialized.
+ *
+ * @param[out] dev          device descriptor of sensor to reset
+ *
+ * @return                  0 on success
+ * @return                  -1 on error
+ */
+int hdc1000_reset(hdc1000_t *dev);
+
+/**
+ * @brief Trigger the measurements.
+ * Conversion Time by 14 bit resolution is 6.50ms.
+ *
+ * @param[in]  dev          device descriptor of sensor
+ *
+ * @return                  0 on success
+ * @return                  -1 on error
+ */
+int hdc1000_startmeasure(hdc1000_t *dev);
+
+/**
+ * @brief Read sensor's data.
+ *
+ * @param[in]  dev          device descriptor of sensor
+ *
+ * @return                  0 on success
+ * @return                  -1 on error
+ */
+int hdc1000_read(hdc1000_t *dev, uint16_t *rawtemp, uint16_t *rawhum);
+
+/**
+ * @brief Convert raw sensor values to temperature and humidity.
+ *
+ * @param[in]  rawtemp      raw temperature value
+ * @param[in]  rawhum       raw humidity value
+ * @param[out] temp         converted temperature*100
+ * @param[out] hum          converted humidity*100
+ */
+void hdc1000_convert(uint16_t rawtemp, uint16_t rawhum,  int *temp, int *hum);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+/** @} */