qiuchengxuan / bmp280 Goto Github PK

In your test you have RawPressure::from_bytes(&hex!("4E 54 80")) I make that this should have a value of 320840 but it actually gives 320960.
repo:

#[test]
fn parse_raw_pressure() {
    use super::RawPressure;
    let raw_pressure = RawPressure::from_bytes(&hex!("4E 54 80"));
    assert_eq!(320840, raw_pressure.0);
}

I think this is because we are not taking the top nibble from the xlsb register.

I think that this:

pub fn from_bytes(bytes: &[u8]) -> Self {
      Self((bytes[0] as i32) << 12 | (bytes[1] as i32) << 4 | (bytes[2] as i32))
  }

should be changed to something like this:

 pub fn from_bytes(bytes: &[u8]) -> Self {
      let msb = (bytes[0] as i32) << 12;
      let lsb = (bytes[1] as i32) << 4;
      let xlsb = (bytes[2] as i32) >> 4;

      Self(msb | lsb | xlsb)
  }

Am I right in thinking that as it stands it is not possible to use this lib with a BMP280 connected to an i2c bus?

I am fairly new to rust but from looking over the code I think I would need to implement an I2cBus that implemented the Bus trait.

I am happy to try and put together a PR but wanted to reach out first as I might need some help, guidance as this is my first embedded rust project.