/*
* Driver for Bosch Sensortec BME680 digital temperature, humity, pressure and
* gas sensor connected to I2C or SPI
*
* Part of esp-open-rtos [https://github.com/SuperHouse/esp-open-rtos]
*
* PLEASE NOTE:
* Due to the complexity of the sensor output value computation based on many
* calibration parameters, the original Bosch Sensortec BME680 driver that is
* released as open source [https://github.com/BoschSensortec/BME680_driver]
* and integrated for internal use. Please note the license of this part, which
* is an extended BSD license and can be found in each of that source files.
*
* ---------------------------------------------------------------------------
*
* The BSD License (3-clause license)
*
* Copyright (c) 2017 Gunar Schorcht (https://github.com/gschorcht]
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. Neither the name of the copyright holder 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.
*/
#include <string.h>
#include "bme680_drv.h"
#include "FreeRTOS.h"
#include "task.h"
#include "espressif/esp_common.h"
#include "espressif/sdk_private.h"
#ifdef BME680_DEBUG
#define debug(s, f, ...) printf("%s %s: " s "\n", "BME680", f, ## __VA_ARGS__)
#else
#define debug(s, f, ...)
#endif
#define error(s, f, ...) printf("%s %s: " s "\n", "BME680", f, ## __VA_ARGS__)
#define BME680_BG_TASK_PRIORITY 9
/**
* Forward declation of internal functions used by embedded Bosch Sensortec BME680 driver.
*/
static void bme680_user_delay_ms(uint32_t period);
static int8_t bme680_user_spi_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len);
static int8_t bme680_user_spi_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len);
static int8_t bme680_user_i2c_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len);
static int8_t bme680_user_i2c_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len);
/**
* Sensor data structures
*/
bme680_sensor_t bme680_sensors[BME680_MAX_SENSORS];
/** */
static bool bme680_valid_sensor (uint32_t sensor, const char* function)
{
if (sensor < 0 || sensor > BME680_MAX_SENSORS)
{
debug("Wrong sensor id %d.", function, sensor);
return false;
}
if (!bme680_sensors[sensor].active)
{
debug("Sensor with id %d is not active.", function, sensor);
return false;
}
return true;
}
static bool bme680_is_available (uint32_t id)
{
struct bme680_dev *dev = &bme680_sensors[id].dev;
if (!bme680_valid_sensor(id, __FUNCTION__) ||
bme680_get_regs(BME680_CHIP_ID_ADDR, &dev->chip_id, 1, dev) != BME680_OK)
{
return false;
}
return true;
}
static void bme680_compute_values (uint8_t id, struct bme680_field_data* data)
{
if (!bme680_valid_sensor(id, __FUNCTION__) || !data)
return;
bme680_value_set_t act;
bme680_value_set_t avg = bme680_sensors[id].average;
float w = bme680_sensors[id].average_weight;
act.temperature = bme680_sensors[id].dev.tph_sett.os_temp ? data->temperature / 100.0f : 0;
act.pressure = bme680_sensors[id].dev.tph_sett.os_pres ? data->pressure / 100.0f : 0;
act.humidity = bme680_sensors[id].dev.tph_sett.os_hum ? data->humidity / 1000.0f : 0;
act.gas = bme680_sensors[id].dev.gas_sett.heatr_dur ? data->gas_resistance : 0;
if (bme680_sensors[id].average_first_measurement ||
!bme680_sensors[id].average_computation)
{
bme680_sensors[id].average_first_measurement = false;
avg = act;
}
else
{
avg.temperature = w * act.temperature + (1-w) * avg.temperature;
avg.humidity = w * act.humidity + (1-w) * avg.humidity;
avg.pressure = w * act.pressure + (1-w) * avg.pressure;
avg.gas = w * act.gas + (1-w) * avg.gas;
}
bme680_sensors[id].actual = act;
bme680_sensors[id].average = avg;
}
static void bme680_background_task (void *pvParameters)
{
uint32_t id = (uint32_t)pvParameters;
uint32_t next_time = sdk_system_get_time ();
while (1)
{
debug("%.3f Sensor %d", __FUNCTION__, (double)sdk_system_get_time()*1e-3, id);
struct bme680_dev* dev = &bme680_sensors[id].dev;
struct bme680_field_data data;
uint8_t set_required_settings;
int8_t rslt = BME680_OK;
/* Select the power mode */
/* Must be set before writing the sensor configuration */
dev->power_mode = BME680_FORCED_MODE;
debug ("Using oversampling rates: %d %d %d", __FUNCTION__,
bme680_sensors[id].dev.tph_sett.os_temp,
bme680_sensors[id].dev.tph_sett.os_pres,
bme680_sensors[id].dev.tph_sett.os_hum);
/* Set the required sensor settings needed */
set_required_settings = BME680_OST_SEL |
BME680_OSP_SEL |
BME680_OSH_SEL |
BME680_FILTER_SEL |
BME680_GAS_SENSOR_SEL;
/* Set the desired sensor configuration */
rslt = bme680_set_sensor_settings(set_required_settings, dev);
/* Set the power mode to forced mode to trigger one TPHG measurement cycle */
rslt = bme680_set_sensor_mode(dev);
/* Get the total measurement duration so as to sleep or wait till the
* measurement is complete */
uint16_t meas_period;
bme680_get_profile_dur(&meas_period, dev);
vTaskDelay(meas_period/portTICK_PERIOD_MS); /* Delay till the measurement is ready */
if ((rslt = bme680_get_sensor_data(&data, dev)) == BME680_OK)
{
bme680_compute_values(id, &data);
debug("%d ms: %.2f C, %.2f Percent, %.2f hPa, %.2f Ohm", __FUNCTION__,
sdk_system_get_time (),
bme680_sensors[id].actual.temperature,
bme680_sensors[id].actual.humidity,
bme680_sensors[id].actual.pressure,
bme680_sensors[id].actual.gas);
if (bme680_sensors[id].cb_function)
bme680_sensors[id].cb_function(id,
bme680_sensors[id].actual,
bme680_sensors[id].average);
}
else
error("Could not get data from sensor with id %d", __FUNCTION__,id);
/* Compute next measurement time as well as remaining cycle time*/
uint32_t system_time = sdk_system_get_time ();
uint32_t remaining_time;
next_time = next_time + bme680_sensors[id].period*1000; // in us
if (next_time < system_time)
// in case of timer overflow
remaining_time = UINT32_MAX - system_time + next_time;
else
// normal case
remaining_time = next_time - system_time;
/* Delay the background task by the cycle time */
vTaskDelay(remaining_time/1000/portTICK_PERIOD_MS);
}
}
bool bme680_init_driver()
{
for (int id=0; id < BME680_MAX_SENSORS; id++)
bme680_sensors[id].active = false;
return true;
}
uint32_t bme680_create_sensor(uint8_t bus, uint8_t addr, uint8_t cs)
{
static uint32_t id;
static char bg_task_name[20];
// search for first free sensor data structure
for (id=0; id < BME680_MAX_SENSORS; id++)
{
debug("id=%d active=%d", __FUNCTION__, id, bme680_sensors[id].active);
if (!bme680_sensors[id].active)
break;
}
debug("id=%d", __FUNCTION__, id);
if (id == BME680_MAX_SENSORS)
{
debug("No more sensor data structures available.", __FUNCTION__);
return -1;
}
// init sensor data structure
bme680_sensors[id].bus = bus;
bme680_sensors[id].addr = addr;
bme680_sensors[id].period = 1000;
bme680_sensors[id].average_computation = true;
bme680_sensors[id].average_first_measurement = true;
bme680_sensors[id].average_weight = 0.2;
bme680_sensors[id].cb_function = NULL;
bme680_sensors[id].bg_task = NULL;
bme680_sensors[id].dev.dev_id = id;
if (bme680_sensors[id].addr)
{
// I2C interface used
bme680_sensors[id].addr = addr;
bme680_sensors[id].dev.intf = BME680_I2C_INTF;
bme680_sensors[id].dev.read = bme680_user_i2c_read;
bme680_sensors[id].dev.write = bme680_user_i2c_write;
bme680_sensors[id].dev.delay_ms = bme680_user_delay_ms;
}
else
{
// SPI interface used
bme680_sensors[id].spi_cs_pin = cs;
bme680_sensors[id].dev.intf = BME680_SPI_INTF;
bme680_sensors[id].dev.read = bme680_user_spi_read;
bme680_sensors[id].dev.write = bme680_user_spi_write;
bme680_sensors[id].dev.delay_ms = bme680_user_delay_ms;
gpio_enable(bme680_sensors[id].spi_cs_pin, GPIO_OUTPUT);
gpio_write (bme680_sensors[id].spi_cs_pin, true);
}
// initialize embedded Bosch Sensortec driver
if (bme680_init(&bme680_sensors[id].dev))
{
error("Could not initialize the sensor device with id %d", __FUNCTION__, id);
return -1;
}
bme680_sensors[id].active = true;
/* Set the default temperature, pressure and humidity settings */
bme680_set_oversampling_rates (id, os_1x, os_1x, os_1x);
bme680_set_filter_size (id, iir_size_3);
/* Set heater default profile 320 degree Celcius for 150 ms */
bme680_set_heater_profile (id, 320, 150);
// check whether sensor is available
if (!bme680_is_available(id))
{
debug("Sensor with id %d is not available", __FUNCTION__, id);
bme680_sensors[id].active = false;
return -1;
}
snprintf (bg_task_name, 20, "bme680_bg_task_%d", id);
if (xTaskCreate (bme680_background_task, bg_task_name, 256, (void*)id,
BME680_BG_TASK_PRIORITY,
&bme680_sensors[id].bg_task) != pdPASS)
{
vTaskDelete(bme680_sensors[id].bg_task);
error("Could not create the background task %s for sensor with id %d\n",
__FUNCTION__, bg_task_name, id);
bme680_sensors[id].active = false;
return false;
}
return id;
}
bool bme680_delete_sensor(uint32_t sensor)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
bme680_sensors[sensor].active = false;
if (bme680_sensors[sensor].bg_task)
vTaskDelete(bme680_sensors[sensor].bg_task);
return true;
}
bool bme680_set_measurement_period (uint32_t sensor, uint32_t period)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
if (period < 20)
error("Period of %d ms is less than the minimum "
"period of 20 ms for sensor with id %d.",
__FUNCTION__, period, sensor);
bme680_sensors[sensor].period = period;
return true;
}
bool bme680_set_callback_function (uint32_t sensor, bme680_cb_function_t bme680_user_function)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
bme680_sensors[sensor].cb_function = bme680_user_function;
debug("Set callback function done.", __FUNCTION__);
return false;
}
bool bme680_get_values(uint32_t sensor, bme680_value_set_t *actual, bme680_value_set_t *average)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
if (actual) *actual = bme680_sensors[sensor].actual;
if (average) *average = bme680_sensors[sensor].average;
return true;
}
bool bme680_enable_average_computation (uint32_t sensor, bool enabled)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
bme680_sensors[sensor].average_computation = enabled;
bme680_sensors[sensor].average_first_measurement = enabled;
return true;
}
bool bme680_set_average_weight (uint32_t sensor, float weight)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
bme680_sensors[sensor].average_first_measurement = true;
bme680_sensors[sensor].average_weight = weight;
return true;
}
bool bme680_set_oversampling_rates (uint32_t sensor,
bme680_oversampling_t ost,
bme680_oversampling_t osp,
bme680_oversampling_t osh)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
/* Set the temperature, pressure and humidity settings */
bme680_sensors[sensor].dev.tph_sett.os_temp = ost;
bme680_sensors[sensor].dev.tph_sett.os_pres = osp;
bme680_sensors[sensor].dev.tph_sett.os_hum = osh;
debug ("Setting oversampling rates done: osrt=%d osp=%d osrh=%d", __FUNCTION__,
bme680_sensors[sensor].dev.tph_sett.os_temp,
bme680_sensors[sensor].dev.tph_sett.os_pres,
bme680_sensors[sensor].dev.tph_sett.os_hum);
bme680_sensors[sensor].average_first_measurement = true;
return true;
}
bool bme680_set_heater_profile (uint32_t sensor, uint16_t temperature, uint16_t duration)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
/* Set the temperature, pressure and humidity settings */
bme680_sensors[sensor].dev.gas_sett.heatr_temp = temperature; /* degree Celsius */
bme680_sensors[sensor].dev.gas_sett.heatr_dur = duration; /* milliseconds */
debug ("Setting heater profile done: temperature=%d duration=%d", __FUNCTION__,
bme680_sensors[sensor].dev.gas_sett.heatr_temp,
bme680_sensors[sensor].dev.gas_sett.heatr_dur);
/* Set the remaining default gas sensor settings and link the heating profile */
if (temperature == 0 || duration == 0)
bme680_sensors[sensor].dev.gas_sett.run_gas = BME680_DISABLE_GAS_MEAS;
else
bme680_sensors[sensor].dev.gas_sett.run_gas = BME680_ENABLE_GAS_MEAS;
bme680_sensors[sensor].average_first_measurement = true;
return true;
}
bool bme680_set_filter_size(uint32_t sensor, bme680_filter_size_t size)
{
if (!bme680_valid_sensor(sensor, __FUNCTION__))
return false;
/* Set the temperature, pressure and humidity settings */
bme680_sensors[sensor].dev.tph_sett.filter = size;
debug ("Setting filter size done: size=%d", __FUNCTION__,
bme680_sensors[sensor].dev.tph_sett.filter);
bme680_sensors[sensor].average_first_measurement = true;
return true;
}
/**
* Internal functions used by embedded Bosch Sensortec BME680 driver.
*/
static void bme680_user_delay_ms(uint32_t period)
{
/*
* Return control or wait,
* for a period amount of milliseconds
*/
vTaskDelay(period / portTICK_PERIOD_MS);
}
#define BME680_SPI_BUF_SIZE 64 // SPI register data buffer size of ESP866
static const spi_settings_t bus_settings = {
.mode = SPI_MODE0,
.freq_divider = SPI_FREQ_DIV_10M,
.msb = true,
.minimal_pins = true,
.endianness = SPI_LITTLE_ENDIAN
};
static int8_t bme680_user_spi_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
/*
* The parameter dev_id can be used as a variable to select which Chip Select pin has
* to be set low to activate the relevant device on the SPI bus
*/
/*
* Data on the bus should be like
* |----------------+---------------------+-------------|
* | MOSI | MISO | Chip Select |
* |----------------+---------------------|-------------|
* | (don't care) | (don't care) | HIGH |
* | (reg_addr) | (don't care) | LOW |
* | (don't care) | (reg_data[0]) | LOW |
* | (....) | (....) | LOW |
* | (don't care) | (reg_data[len - 1]) | LOW |
* | (don't care) | (don't care) | HIGH |
* |----------------+---------------------|-------------|
*/
// debug("dev_id=%d, reg_addr=%0x, len=%d\n", __FUNCTION__, dev_id, reg_addr, len);
if (len >= BME680_SPI_BUF_SIZE)
{
error("Error on read from SPI slave on bus 1. Tried to transfer more"
"than %d byte in one read operation.", __FUNCTION__, BME680_SPI_BUF_SIZE);
return -1;
}
spi_settings_t old_settings;
static uint8_t mosi[BME680_SPI_BUF_SIZE];
static uint8_t miso[BME680_SPI_BUF_SIZE];
memset (mosi, 0xff, BME680_SPI_BUF_SIZE);
memset (miso, 0xff, BME680_SPI_BUF_SIZE);
mosi[0] = reg_addr;
uint8_t bus = bme680_sensors[dev_id].bus;
uint8_t spi_cs_pin = bme680_sensors[dev_id].spi_cs_pin;
spi_get_settings(bus, &old_settings);
spi_set_settings(bus, &bus_settings);
gpio_write(spi_cs_pin, false);
size_t success = spi_transfer (bus, (const void*)mosi, (void*)miso, len+1, SPI_8BIT);
gpio_write(spi_cs_pin, true);
spi_set_settings(bus, &old_settings);
if (!success)
{
error("Could not read data from SPI bus %d", __FUNCTION__, bus);
return -1;
}
for (int i=0; i < len; i++)
reg_data[i] = miso[i+1];
# ifdef BME680_DEBUG
printf("BME680 %s: Read the following bytes: ", __FUNCTION__);
printf("%0x ", reg_addr);
for (int i=0; i < len; i++)
printf("%0x ", reg_data[i]);
printf("\n");
# endif
return 0;
}
static int8_t bme680_user_spi_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
/*
* The parameter dev_id can be used as a variable to select which Chip Select pin has
* to be set low to activate the relevant device on the SPI bus
*/
/*
* Data on the bus should be like
* |---------------------+--------------+-------------|
* | MOSI | MISO | Chip Select |
* |---------------------+--------------|-------------|
* | (don't care) | (don't care) | HIGH |
* | (reg_addr) | (don't care) | LOW |
* | (reg_data[0]) | (don't care) | LOW |
* | (....) | (....) | LOW |
* | (reg_data[len - 1]) | (don't care) | LOW |
* | (don't care) | (don't care) | HIGH |
* |---------------------+--------------|-------------|
*/
static uint8_t mosi[BME680_SPI_BUF_SIZE];
if (len >= BME680_SPI_BUF_SIZE)
{
error("Error on write to SPI slave on bus 1. Tried to transfer more"
"than %d byte in one write operation.", __FUNCTION__, BME680_SPI_BUF_SIZE);
return -1;
}
mosi[0] = reg_addr;
for (int i = 0; i < len; i++)
mosi[i+1] = reg_data[i];
# ifdef BME680_DEBUG
printf("BME680 %s: Write the following bytes: ", __FUNCTION__);
for (int i = 0; i < len+1; i++)
printf("%0x ", mosi[i]);
printf("\n");
# endif
spi_settings_t old_settings;
uint8_t bus = bme680_sensors[dev_id].bus;
uint8_t spi_cs_pin = bme680_sensors[dev_id].spi_cs_pin;
spi_get_settings(bus, &old_settings);
spi_set_settings(bus, &bus_settings);
gpio_write(spi_cs_pin, false);
size_t success = spi_transfer (bus, (const void*)mosi, NULL, len+1, SPI_8BIT);
gpio_write(spi_cs_pin, true);
spi_set_settings(bus, &old_settings);
if (!success)
{
error("Could not write data to SPI bus %d", __FUNCTION__, bus);
return -1;
}
return 0;
}
static int8_t bme680_user_i2c_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
/*
* The parameter dev_id can be used as a variable to store the I2C address of the device
*/
/*
* Data on the bus should be like
* |------------+---------------------|
* | I2C action | Data |
* |------------+---------------------|
* | Start | - |
* | Write | (reg_addr) |
* | Stop | - |
* | Start | - |
* | Read | (reg_data[0]) |
* | Read | (....) |
* | Read | (reg_data[len - 1]) |
* | Stop | - |
* |------------+---------------------|
*/
debug ("Read %d byte from i2c slave on bus %d with addr %0x.",
__FUNCTION__, len, bme680_sensors[dev_id].bus, bme680_sensors[dev_id].addr);
int result = i2c_slave_read(bme680_sensors[dev_id].bus,
bme680_sensors[dev_id].addr,
®_addr, reg_data, len);
if (result)
{
error("Error %d on read %d byte from I2C slave on bus %d with addr %0x.",
__FUNCTION__, result, len, bme680_sensors[dev_id].bus, bme680_sensors[dev_id].addr);
return result;
}
# ifdef BME680_DEBUG
printf("BME680 %s: Read following bytes: ", __FUNCTION__);
printf("%0x ", reg_addr);
for (int i=0; i < len; i++)
printf("%0x ", reg_data[i]);
printf("\n");
# endif
return result;
}
static int8_t bme680_user_i2c_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
/*
* The parameter dev_id can be used as a variable to store the I2C address of the device
*/
/*
* Data on the bus should be like
* |------------+---------------------|
* | I2C action | Data |
* |------------+---------------------|
* | Start | - |
* | Write | (reg_addr) |
* | Write | (reg_data[0]) |
* | Write | (....) |
* | Write | (reg_data[len - 1]) |
* | Stop | - |
* |------------+---------------------|
*/
debug ("Write %d byte to i2c slave on bus %d with addr %0x.",
__FUNCTION__, len, bme680_sensors[dev_id].bus, bme680_sensors[dev_id].addr);
int result = i2c_slave_write(bme680_sensors[dev_id].bus,
bme680_sensors[dev_id].addr,
®_addr, reg_data, len);
if (result)
{
error("Error %d on write to i2c slave on bus %d with addr %0x.",
__FUNCTION__, result, bme680_sensors[dev_id].bus, bme680_sensors[dev_id].addr);
return result;
}
# ifdef BME680_DEBUG
printf("BME680 %s: Wrote the following bytes: ", __FUNCTION__);
printf("%0x ", reg_addr);
for (int i=0; i < len; i++)
printf("%0x ", reg_data[i]);
printf("\n");
# endif
return result;
}