Add support for SPI.

example/src/main.rs

@@ -1,8 +1,8 @@
-extern crate linux_embedded_hal as hal;
 extern crate bme280;
+extern crate linux_embedded_hal as hal;
 
+use bme280::i2c::BME280;
 use hal::{Delay, I2cdev};
-use bme280::BME280;
 use std::thread;
 use std::time::Duration;
 

src/i2c.rs

@@ -0,0 +1,115 @@
+//! BME280 driver for sensors attached via I2C.
+
+use embedded_hal::blocking::delay::DelayMs;
+use embedded_hal::blocking::i2c::{Read, Write, WriteRead};
+
+use super::{
+    BME280Common, Error, Interface, Measurements, BME280_H_CALIB_DATA_LEN,
+    BME280_P_T_CALIB_DATA_LEN, BME280_P_T_H_DATA_LEN,
+};
+
+const BME280_I2C_ADDR_PRIMARY: u8 = 0x76;
+const BME280_I2C_ADDR_SECONDARY: u8 = 0x77;
+
+/// Representation of a BME280
+#[derive(Debug, Default)]
+pub struct BME280<I2C, D> {
+    common: BME280Common<I2CInterface<I2C>, D>,
+}
+
+impl<I2C, D, E> BME280<I2C, D>
+where
+    I2C: Read<Error = E> + Write<Error = E> + WriteRead<Error = E>,
+    D: DelayMs<u8>,
+{
+    /// Create a new BME280 struct using the primary I²C address `0x76`
+    pub fn new_primary(i2c: I2C, delay: D) -> Self {
+        Self::new(i2c, BME280_I2C_ADDR_PRIMARY, delay)
+    }
+
+    /// Create a new BME280 struct using the secondary I²C address `0x77`
+    pub fn new_secondary(i2c: I2C, delay: D) -> Self {
+        Self::new(i2c, BME280_I2C_ADDR_SECONDARY, delay)
+    }
+
+    /// Create a new BME280 struct using a custom I²C address
+    pub fn new(i2c: I2C, address: u8, delay: D) -> Self {
+        BME280 {
+            common: BME280Common {
+                interface: I2CInterface { i2c, address },
+                delay,
+                calibration: None,
+            },
+        }
+    }
+
+    /// Initializes the BME280
+    pub fn init(&mut self) -> Result<(), Error<E>> {
+        self.common.init()
+    }
+
+    /// Captures and processes sensor data for temperature, pressure, and humidity
+    pub fn measure(&mut self) -> Result<Measurements<E>, Error<E>> {
+        self.common.measure()
+    }
+}
+
+/// Register access functions for I2C
+#[derive(Debug, Default)]
+struct I2CInterface<I2C> {
+    /// concrete I²C device implementation
+    i2c: I2C,
+    /// I²C device address
+    address: u8,
+}
+
+impl<I2C, E> Interface for I2CInterface<I2C>
+where
+    I2C: Read<Error = E> + Write<Error = E> + WriteRead<Error = E>,
+{
+    type Error = E;
+
+    fn read_register(&mut self, register: u8) -> Result<u8, Error<E>> {
+        let mut data: [u8; 1] = [0];
+        self.i2c
+            .write_read(self.address, &[register], &mut data)
+            .map_err(Error::Bus)?;
+        Ok(data[0])
+    }
+
+    fn read_data(&mut self, register: u8) -> Result<[u8; BME280_P_T_H_DATA_LEN], Error<E>> {
+        let mut data: [u8; BME280_P_T_H_DATA_LEN] = [0; BME280_P_T_H_DATA_LEN];
+        self.i2c
+            .write_read(self.address, &[register], &mut data)
+            .map_err(Error::Bus)?;
+        Ok(data)
+    }
+
+    fn read_pt_calib_data(
+        &mut self,
+        register: u8,
+    ) -> Result<[u8; BME280_P_T_CALIB_DATA_LEN], Error<E>> {
+        let mut data: [u8; BME280_P_T_CALIB_DATA_LEN] = [0; BME280_P_T_CALIB_DATA_LEN];
+        self.i2c
+            .write_read(self.address, &[register], &mut data)
+            .map_err(Error::Bus)?;
+        Ok(data)
+    }
+
+    fn read_h_calib_data(
+        &mut self,
+        register: u8,
+    ) -> Result<[u8; BME280_H_CALIB_DATA_LEN], Error<E>> {
+        let mut data: [u8; BME280_H_CALIB_DATA_LEN] = [0; BME280_H_CALIB_DATA_LEN];
+        self.i2c
+            .write_read(self.address, &[register], &mut data)
+            .map_err(Error::Bus)?;
+        Ok(data)
+    }
+
+    fn write_register(&mut self, register: u8, payload: u8) -> Result<(), Error<E>> {
+        self.i2c
+            .write(self.address, &[register, payload])
+            .map_err(Error::Bus)
+    }
+}