/*
- Linux userspace test code, simple and mose code directy from the doco.
- compile like this: gcc linux_userspace.c ../bme280.c -I ../ -o bme280
- tested: Raspberry Pi.
- Use like: ./bme280 /dev/i2c-0
+ Linux userspace test code, simple and mose code directy from the doco.
+ compile like this: gcc linux_userspace.c ../bme280.c -I ../ -o bme280
+ tested: Raspberry Pi.
+ Use like: ./bme280 /dev/i2c-0
*/
-#include "bme280.h"
+
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <fcntl.h>
+#include "bme280.h"
int fd;
int8_t user_i2c_read(uint8_t id, uint8_t reg_addr, uint8_t *data, uint16_t len)
{
- write(fd, ®_addr,1);
- read(fd, data, len);
- return 0;
+ if (write(fd, ®_addr, sizeof(reg_addr)) < sizeof(reg_addr))
+ return BME280_E_COMM_FAIL;
+ if (read(fd, data, len) < len)
+ return BME280_E_COMM_FAIL;
+ return BME280_OK;
}
void user_delay_ms(uint32_t period)
{
- usleep(period*1000);
+ usleep(period * 1000);
}
int8_t user_i2c_write(uint8_t id, uint8_t reg_addr, uint8_t *data, uint16_t len)
{
- int8_t *buf;
- buf = malloc(len +1);
- buf[0] = reg_addr;
- memcpy(buf +1, data, len);
- write(fd, buf, len +1);
- free(buf);
- return 0;
+ int8_t *buf;
+ buf = malloc(len + 1);
+ buf[0] = reg_addr;
+ memcpy(buf + 1, data, len);
+ if (write(fd, buf, len + 1) < len)
+ return BME280_E_COMM_FAIL;
+ free(buf);
+ return BME280_OK;
}
void print_sensor_data(struct bme280_data *comp_data)
{
+ float temp, press, hum;
#ifdef BME280_FLOAT_ENABLE
- printf("temp %0.2f, p %0.2f, hum %0.2f\r\n",comp_data->temperature, comp_data->pressure, comp_data->humidity);
+ temp = comp_data->temperature;
+ press = 0.01 * comp_data->pressure;
+ hum = comp_data->humidity;
+#else
+#ifdef BME280_64BIT_ENABLE
+ temp = 0.01f * comp_data->temperature;
+ press = 0.0001f * comp_data->pressure;
+ hum = 1.0f / 1024.0f * comp_data->humidity;
#else
- printf("temp %ld, p %ld, hum %ld\r\n",comp_data->temperature, comp_data->pressure, comp_data->humidity);
+ temp = 0.01f * comp_data->temperature;
+ press = 0.01f * comp_data->pressure;
+ hum = 1.0f / 1024.0f * comp_data->humidity;
#endif
+#endif
+ printf("%0.2lf deg C, %0.2lf hPa, %0.2lf%%\n", temp, press, hum);
}
int8_t stream_sensor_data_forced_mode(struct bme280_dev *dev)
{
- int8_t rslt;
- uint8_t settings_sel;
- struct bme280_data comp_data;
+ int8_t rslt;
+ uint8_t settings_sel;
+ struct bme280_data comp_data;
- /* Recommended mode of operation: Indoor navigation */
- dev->settings.osr_h = BME280_OVERSAMPLING_1X;
- dev->settings.osr_p = BME280_OVERSAMPLING_16X;
- dev->settings.osr_t = BME280_OVERSAMPLING_2X;
- dev->settings.filter = BME280_FILTER_COEFF_16;
+ /* Recommended mode of operation: Indoor navigation */
+ dev->settings.osr_h = BME280_OVERSAMPLING_1X;
+ dev->settings.osr_p = BME280_OVERSAMPLING_16X;
+ dev->settings.osr_t = BME280_OVERSAMPLING_2X;
+ dev->settings.filter = BME280_FILTER_COEFF_16;
- settings_sel = BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL | BME280_OSR_HUM_SEL | BME280_FILTER_SEL;
+ settings_sel = BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL | BME280_OSR_HUM_SEL | BME280_FILTER_SEL;
- rslt = bme280_set_sensor_settings(settings_sel, dev);
+ rslt = bme280_set_sensor_settings(settings_sel, dev);
+ if (rslt != BME280_OK)
+ {
+ fprintf(stderr, "Failed to set sensor settings (code %+d).", rslt);
+ return rslt;
+ }
- printf("Temperature, Pressure, Humidity\r\n");
- /* Continuously stream sensor data */
- while (1) {
- rslt = bme280_set_sensor_mode(BME280_FORCED_MODE, dev);
- /* Wait for the measurement to complete and print data @25Hz */
- dev->delay_ms(40);
- rslt = bme280_get_sensor_data(BME280_ALL, &comp_data, dev);
- print_sensor_data(&comp_data);
- }
- return rslt;
+ printf("Temperature, Pressure, Humidity\n");
+ /* Continuously stream sensor data */
+ while (1)
+ {
+ rslt = bme280_set_sensor_mode(BME280_FORCED_MODE, dev);
+ if (rslt != BME280_OK)
+ {
+ fprintf(stderr, "Failed to set sensor mode (code %+d).", rslt);
+ break;
+ }
+ /* Wait for the measurement to complete and print data @25Hz */
+ dev->delay_ms(40);
+ rslt = bme280_get_sensor_data(BME280_ALL, &comp_data, dev);
+ if (rslt != BME280_OK)
+ {
+ fprintf(stderr, "Failed to get sensor data (code %+d).", rslt);
+ break;
+ }
+ print_sensor_data(&comp_data);
+ }
+ return rslt;
}
int main(int argc, char* argv[])
{
- struct bme280_dev dev;
- int8_t rslt = BME280_OK;
+ struct bme280_dev dev;
+ int8_t rslt = BME280_OK;
+
+ if (argc < 2)
+ {
+ fprintf(stderr, "Missing argument for i2c bus.\n");
+ exit(1);
+ }
+
+ // make sure to select BME280_I2C_ADDR_PRIM
+ // or BME280_I2C_ADDR_SEC as needed
+ dev.dev_id =
+#if 1
+ BME280_I2C_ADDR_PRIM
+#else
+ BME280_I2C_ADDR_SEC
+#endif
+ ;
- if ((fd = open(argv[1], O_RDWR)) < 0) {
- printf("Failed to open the i2c bus %s", argv[1]);
- exit(1);
- }
- if (ioctl(fd, I2C_SLAVE, 0x76) < 0) {
- printf("Failed to acquire bus access and/or talk to slave.\n");
- exit(1);
- }
- dev.dev_id = BME280_I2C_ADDR_PRIM;
- dev.intf = BME280_I2C_INTF;
- dev.read = user_i2c_read;
- dev.write = user_i2c_write;
- dev.delay_ms = user_delay_ms;
+ dev.intf = BME280_I2C_INTF;
+ dev.read = user_i2c_read;
+ dev.write = user_i2c_write;
+ dev.delay_ms = user_delay_ms;
- rslt = bme280_init(&dev);
- stream_sensor_data_forced_mode(&dev);
+ if ((fd = open(argv[1], O_RDWR)) < 0)
+ {
+ fprintf(stderr, "Failed to open the i2c bus %s\n", argv[1]);
+ exit(1);
+ }
+ if (ioctl(fd, I2C_SLAVE, dev.dev_id) < 0)
+ {
+ fprintf(stderr, "Failed to acquire bus access and/or talk to slave.\n");
+ exit(1);
+ }
+
+ rslt = bme280_init(&dev);
+ if (rslt != BME280_OK)
+ {
+ fprintf(stderr, "Failed to initialize the device (code %+d).\n", rslt);
+ exit(1);
+ }
+ rslt = stream_sensor_data_forced_mode(&dev);
+ if (rslt != BME280_OK)
+ {
+ fprintf(stderr, "Failed to stream sensor data (code %+d).\n", rslt);
+ exit(1);
+ }
+ return 0;
}