fixed i2c addr, added wait for sensor to take initial readings before requesting them

src/main.c

@@ -35,7 +35,8 @@ int8_t check_file_exists(const char *filename)
 
 void user_delay_ms(uint32_t period)
 {
-  usleep(period*1000);
+    usleep(period*1000); // if using gnu99
+    //sleep(period*1000); // if using c99
 }
 
 #ifdef BME280_FLOAT_ENABLE
@@ -210,6 +211,7 @@ int8_t read_sensor_data_normal_mode(struct bme280_dev *dev)
     settings_sel |= BME280_FILTER_SEL;
     readings_result = bme280_set_sensor_settings(settings_sel, dev);
     readings_result = bme280_set_sensor_mode(BME280_NORMAL_MODE, dev);
+    dev->delay_ms(200); // wait for first measurement
     readings_result = bme280_get_sensor_data(BME280_ALL, &sensor_readings_data, dev);
     print_sensor_data(&sensor_readings_data);
     //save_data_to_json_file(&sensor_readings_data);
@@ -226,13 +228,13 @@ int main(int argc, char* argv[])
         printf("Failed to open the i2c bus %s", argv[1]);
         exit(1);
     }
-    if (ioctl(file_descriptor, I2C_SLAVE, 0x76) < 0) {
+    if (ioctl(file_descriptor, I2C_SLAVE, 0x77) < 0) {
         printf("Failed to acquire bus access and/or talk to slave.\n");
         exit(1);
     }
 
-    dev.dev_id = BME280_I2C_ADDR_PRIM; //0x76
-    //dev.dev_id = BME280_I2C_ADDR_SEC; //0x77
+    //dev.dev_id = BME280_I2C_ADDR_PRIM; //0x76 (if orange/pin 5 is connected to ground on Pi)
+    dev.dev_id = BME280_I2C_ADDR_SEC; //0x77 (if orange/pin 5 is connected to 3.3V on Pi)
     dev.intf = BME280_I2C_INTF;
     dev.read = user_i2c_read;
     dev.write = user_i2c_write;