Merge pull request #65 from Sensirion/merge-sht4x

Support SHT4x

.gitignore

@@ -2,6 +2,8 @@
 /release
 /sht3x/sht3x_example_usage
 /sht3x/user_config.inc
+/sht4x/sht4x_example_usage
+/sht4x/user_config.inc
 /shtc1/shtc1_example_usage
 /shtc1/user_config.inc
 /sht-common/sht_git_version.c

CHANGELOG.md

@@ -5,6 +5,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+ * [`added`]    SHT4x Support
+
 ## [5.1.0] - 2020-06-12
 
  * [`changed`]  Cleanup and better document stm32 sample code

Makefile

@@ -1,4 +1,4 @@
-drivers=sht3x shtc1
+drivers=sht3x sht4x shtc1
 sample-projects=shtc3-stm32-uvision
 clean_drivers=$(foreach d, $(drivers), clean_$(d))
 release_drivers=$(foreach d, $(drivers), release/$(d))

README.md

@@ -17,8 +17,11 @@ cloning the repository.
 ## Repository content
 * `embedded-common` submodule repository for the common embedded driver HAL
 * `sht-common` common files for all SHTxx drivers, humidity conversion functions
-* `sht3x` SHT3x/SHT8x driver related
-* `shtc1` SHTC3/SHTC1/SHTW1/SHTW2 driver related
+* `sht4x` SHT4 driver
+* `sht3x` SHT3x/SHT8x driver
+* `shtc1` SHTC3/SHTC1/SHTW1/SHTW2 driver
+* `utils` Conversion functions (Centigrade to Fahrenheit, %RH relative humidity
+          to aboslute humidity)
 
 ## Collecting resources
 ```

sht4x/Makefile

@@ -0,0 +1,14 @@
+# See user_config.inc for build customization
+-include user_config.inc
+include default_config.inc
+
+
+.PHONY: all clean
+
+all: sht4x_example_usage
+
+sht4x_example_usage: clean
+	$(CC) $(CFLAGS) -o $@ ${sht4x_sources} ${${CONFIG_I2C_TYPE}_sources} ${sht4x_dir}/sht4x_example_usage.c
+
+clean:
+	$(RM) sht4x_example_usage

sht4x/default_config.inc

@@ -0,0 +1,28 @@
+sht_driver_dir ?= ..
+sensirion_common_dir ?= ${sht_driver_dir}/embedded-common
+sht_common_dir ?= ${sht_driver_dir}/sht-common
+sht4x_dir ?= ${sht_driver_dir}/sht4x
+CONFIG_I2C_TYPE ?= hw_i2c
+
+sw_i2c_impl_src ?= ${sensirion_common_dir}/sw_i2c/sensirion_sw_i2c_implementation.c
+hw_i2c_impl_src ?= ${sensirion_common_dir}/hw_i2c/sensirion_hw_i2c_implementation.c
+
+CFLAGS ?= -Os -Wall -fstrict-aliasing -Wstrict-aliasing=1 -Wsign-conversion -fPIC
+CFLAGS += -I${sensirion_common_dir} -I${sht_common_dir} -I${sht4x_dir} \
+          -I${sensirion_common_dir}/${CONFIG_I2C_TYPE}
+
+sensirion_common_sources = ${sensirion_common_dir}/sensirion_arch_config.h \
+                           ${sensirion_common_dir}/sensirion_i2c.h \
+                           ${sensirion_common_dir}/sensirion_common.h \
+                           ${sensirion_common_dir}/sensirion_common.c
+
+sht_common_sources = ${sht_common_dir}/sht_git_version.h \
+                     ${sht_common_dir}/sht_git_version.c
+
+sht4x_sources = ${sensirion_common_sources} ${sht_common_sources} \
+                ${sht4x_dir}/sht4x.h ${sht4x_dir}/sht4x.c
+
+hw_i2c_sources = ${hw_i2c_impl_src}
+sw_i2c_sources = ${sensirion_common_dir}/sw_i2c/sensirion_sw_i2c_gpio.h \
+                 ${sensirion_common_dir}/sw_i2c/sensirion_sw_i2c.c \
+                 ${sw_i2c_impl_src}

sht4x/sht4x.c

@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2020, Sensirion AG
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * * Neither the name of Sensirion AG nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ *
+ * \brief Sensirion SHT4X driver implementation
+ *
+ * This module provides access to the SHT4X functionality over a generic I2C
+ * interface. It supports measurements without clock stretching only.
+ */
+
+#include "sht4x.h"
+#include "sensirion_arch_config.h"
+#include "sensirion_common.h"
+#include "sensirion_i2c.h"
+
+/* all measurement commands return T (CRC) RH (CRC) */
+#define SHT4X_CMD_MEASURE_HPM 0xFD
+#define SHT4X_CMD_MEASURE_LPM 0xE0
+#define SHT4X_CMD_READ_SERIAL 0x89
+#define SHT4X_CMD_DURATION_USEC 1000
+
+#define SHT4X_ADDRESS 0x44
+
+static uint8_t sht4x_cmd_measure = SHT4X_CMD_MEASURE_HPM;
+static uint16_t sht4x_cmd_measure_delay_us = SHT4X_MEASUREMENT_DURATION_USEC;
+
+int16_t sht4x_measure_blocking_read(int32_t* temperature, int32_t* humidity) {
+    int16_t ret;
+
+    ret = sht4x_measure();
+    if (ret)
+        return ret;
+    sensirion_sleep_usec(sht4x_cmd_measure_delay_us);
+    return sht4x_read(temperature, humidity);
+}
+
+int16_t sht4x_measure(void) {
+    return sensirion_i2c_write(SHT4X_ADDRESS, &sht4x_cmd_measure, 1);
+}
+
+int16_t sht4x_read(int32_t* temperature, int32_t* humidity) {
+    uint16_t words[2];
+    int16_t ret = sensirion_i2c_read_words(SHT4X_ADDRESS, words,
+                                           SENSIRION_NUM_WORDS(words));
+    /**
+     * formulas for conversion of the sensor signals, optimized for fixed point
+     * algebra:
+     * Temperature = 175 * S_T / 65535 - 45
+     * Relative Humidity = 125 * (S_RH / 65535) - 6
+     */
+    *temperature = ((21875 * (int32_t)words[0]) >> 13) - 45000;
+    *humidity = ((15625 * (int32_t)words[1]) >> 13) - 6000;
+
+    return ret;
+}
+
+int16_t sht4x_probe(void) {
+    uint32_t serial;
+
+    return sht4x_read_serial(&serial);
+}
+
+void sht4x_enable_low_power_mode(uint8_t enable_low_power_mode) {
+    if (enable_low_power_mode) {
+        sht4x_cmd_measure = SHT4X_CMD_MEASURE_LPM;
+        sht4x_cmd_measure_delay_us = SHT4X_MEASUREMENT_DURATION_LPM_USEC;
+    } else {
+        sht4x_cmd_measure = SHT4X_CMD_MEASURE_HPM;
+        sht4x_cmd_measure_delay_us = SHT4X_MEASUREMENT_DURATION_USEC;
+    }
+}
+
+int16_t sht4x_read_serial(uint32_t* serial) {
+    const uint8_t cmd = SHT4X_CMD_READ_SERIAL;
+    int16_t ret;
+    uint16_t serial_words[SENSIRION_NUM_WORDS(*serial)];
+
+    ret = sensirion_i2c_write(SHT4X_ADDRESS, &cmd, 1);
+    if (ret)
+        return ret;
+
+    sensirion_sleep_usec(SHT4X_CMD_DURATION_USEC);
+    ret = sensirion_i2c_read_words(SHT4X_ADDRESS, serial_words,
+                                   SENSIRION_NUM_WORDS(serial_words));
+    *serial = ((uint32_t)serial_words[0] << 16) | serial_words[1];
+
+    return ret;
+}
+
+const char* sht4x_get_driver_version(void) {
+    return SHT_DRV_VERSION_STR;
+}
+
+uint8_t sht4x_get_configured_address(void) {
+    return SHT4X_ADDRESS;
+}

sht4x/sht4x.h

@@ -0,0 +1,142 @@
+/*
+ * Copyright (c) 2020, Sensirion AG
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * * Neither the name of Sensirion AG nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ *
+ * \brief Sensirion SHT driver interface
+ *
+ * This module provides access to the SHT functionality over a generic I2C
+ * interface. It supports measurements without clock stretching only.
+ */
+
+#ifndef SHT4X_H
+#define SHT4X_H
+
+#include "sensirion_arch_config.h"
+#include "sensirion_i2c.h"
+#include "sht_git_version.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define STATUS_OK 0
+#define STATUS_ERR_BAD_DATA (-1)
+#define STATUS_CRC_FAIL (-2)
+#define STATUS_UNKNOWN_DEVICE (-3)
+#define SHT4X_MEASUREMENT_DURATION_USEC 10000 /* 10ms "high repeatability" */
+#define SHT4X_MEASUREMENT_DURATION_LPM_USEC \
+    2500 /* 2.5ms "low repeatability"       \
+          */
+
+/**
+ * Detects if a sensor is connected by reading out the ID register.
+ * If the sensor does not answer or if the answer is not the expected value,
+ * the test fails.
+ *
+ * @return 0 if a sensor was detected
+ */
+int16_t sht4x_probe(void);
+
+/**
+ * Starts a measurement and then reads out the results. This function blocks
+ * while the measurement is in progress. The duration of the measurement depends
+ * on the sensor in use, please consult the datasheet.
+ * Temperature is returned in [degree Celsius], multiplied by 1000,
+ * and relative humidity in [percent relative humidity], multiplied by 1000.
+ *
+ * @param temperature   the address for the result of the temperature
+ * measurement
+ * @param humidity      the address for the result of the relative humidity
+ * measurement
+ * @return              0 if the command was successful, else an error code.
+ */
+int16_t sht4x_measure_blocking_read(int32_t* temperature, int32_t* humidity);
+
+/**
+ * Starts a measurement in high precision mode. Use sht4x_read() to read out the
+ * values, once the measurement is done. The duration of the measurement depends
+ * on the sensor in use, please consult the datasheet.
+ *
+ * @return     0 if the command was successful, else an error code.
+ */
+int16_t sht4x_measure(void);
+
+/**
+ * Reads out the results of a measurement that was previously started by
+ * sht4x_measure(). If the measurement is still in progress, this function
+ * returns an error.
+ * Temperature is returned in [degree Celsius], multiplied by 1000,
+ * and relative humidity in [percent relative humidity], multiplied by 1000.
+ *
+ * @param temperature   the address for the result of the temperature
+ * measurement
+ * @param humidity      the address for the result of the relative humidity
+ * measurement
+ * @return              0 if the command was successful, else an error code.
+ */
+int16_t sht4x_read(int32_t* temperature, int32_t* humidity);
+
+/**
+ * Enable or disable the SHT's low power mode
+ *
+ * @param enable_low_power_mode 1 to enable low power mode, 0 to disable
+ */
+void sht4x_enable_low_power_mode(uint8_t enable_low_power_mode);
+
+/**
+ * Read out the serial number
+ *
+ * @param serial    the address for the result of the serial number
+ * @return          0 if the command was successful, else an error code.
+ */
+int16_t sht4x_read_serial(uint32_t* serial);
+
+/**
+ * Return the driver version
+ *
+ * @return Driver version string
+ */
+const char* sht4x_get_driver_version(void);
+
+/**
+ * Returns the configured SHT4x address.
+ *
+ * @return SHT4x_ADDRESS
+ */
+uint8_t sht4x_get_configured_address(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* SHT4X_H */