Merge pull request #57 from janwilleke/master

Linux userspace example code

examples/linux_userspace.c

@@ -0,0 +1,100 @@
+/*
+  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 <unistd.h>
+#include <linux/i2c-dev.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <fcntl.h>
+
+int fd;
+
+int8_t user_i2c_read(uint8_t id, uint8_t reg_addr, uint8_t *data, uint16_t len)
+{
+  write(fd, &reg_addr,1);
+  read(fd, data, len);
+  return 0;
+}
+
+void user_delay_ms(uint32_t period)
+{
+  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;
+}
+
+void print_sensor_data(struct bme280_data *comp_data)
+{
+#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);
+#else
+  printf("temp %ld, p %ld, hum %ld\r\n",comp_data->temperature, comp_data->pressure, comp_data->humidity);
+#endif
+}
+
+int8_t stream_sensor_data_forced_mode(struct bme280_dev *dev)
+{
+  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;
+
+  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);
+
+  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;
+}
+
+int main(int argc, char* argv[])
+{
+  struct bme280_dev dev;
+  int8_t rslt = BME280_OK;
+
+  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;
+
+  rslt = bme280_init(&dev);
+  stream_sensor_data_forced_mode(&dev);
+}