bmp5xx 0.1.0

True-to-spec async I2C driver for the BMP580/BMP581/BMP585 barometric pressure sensors.
Documentation 
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// Copyright (C) 2026 Olivér Pirger
// SPDX-License-Identifier: GPL-3.0-or-later

#![no_std]

pub mod error;
pub(crate) mod register;

use byteorder::{ByteOrder, LittleEndian};
use embedded_hal_async::{delay::DelayNs, i2c::I2c};

use crate::{
    error::{
        Error::{self, WriteError},
        Result,
    },
    register::{
        CHIP_ID, CMD, INT_STATUS, ODR_CONFIG, OSR_CONFIG, PRESS_DATA_XLSB, STATUS, TEMP_DATA_XLSB,
    },
};

pub struct Bmp58x<I2C, D> {
    i2c: I2C,
    delay: D,
    addr: u8,
}

impl<I2C, D> Bmp58x<I2C, D>
where
    I2C: I2c,
    D: DelayNs,
{
    pub async fn new(i2c: I2C, delay: D, addr: u8) -> Result<Self> {
        let mut bmp58x = Self { i2c, delay, addr };

        let mut id_buf = [0u8; 1];
        bmp58x
            .i2c
            .write_read(addr, &[CHIP_ID], &mut id_buf)
            .await
            .map_err(|_| Error::ReadError)?;
        match id_buf[0] {
            0x50 | 0x51 => (),
            _ => return Err(Error::InvalidId),
        }

        bmp58x.reset().await?;

        let mut status_buf = [0u8; 1];
        bmp58x
            .i2c
            .write_read(bmp58x.addr, &[STATUS], &mut status_buf)
            .await
            .map_err(|_| Error::ReadError)?;
        if status_buf[0] & 0x02 == 0 || status_buf[0] & 0x04 != 0 {
            return Err(Error::NotReady);
        }

        let mut int_status_buf = [0u8; 1];
        bmp58x
            .i2c
            .write_read(bmp58x.addr, &[INT_STATUS], &mut int_status_buf)
            .await
            .map_err(|_| Error::ReadError)?;
        if int_status_buf[0] & (1 << 4) == 0 {
            return Err(Error::NotReady);
        }

        // switch to standby & disable deep standby
        bmp58x
            .i2c
            .write(bmp58x.addr, &[ODR_CONFIG, 0x80])
            .await
            .map_err(|_| Error::WriteError)?;

        Ok(bmp58x)
    }

    pub async fn reset(&mut self) -> Result<()> {
        // trigger reset
        self.i2c
            .write(self.addr, &[CMD, 0xB6])
            .await
            .map_err(|_| Error::WriteError)?;

        // t_soft_res
        self.delay.delay_ms(2).await;
        Ok(())
    }

    pub async fn temperature(&mut self) -> Result<f32> {
        // switch to standby & disable deep standby
        self.i2c
            .write(self.addr, &[ODR_CONFIG, 0x80])
            .await
            .map_err(|_| Error::WriteError)?;

        // disable pressure measurement
        self.i2c
            .write(self.addr, &[OSR_CONFIG, 0x00])
            .await
            .map_err(|_| Error::WriteError)?;

        // switch to forced & disable deep standby
        self.i2c
            .write(self.addr, &[ODR_CONFIG, 0x82])
            .await
            .map_err(|_| WriteError)?;

        // t_conv_t (hardcoded OSR=1x)
        self.delay.delay_us(1050).await;

        let mut temp_buf = [0u8; 3];
        self.i2c
            .write_read(self.addr, &[TEMP_DATA_XLSB], &mut temp_buf)
            .await
            .map_err(|_| Error::ReadError)?;
        let raw_temp = LittleEndian::read_i24(&temp_buf);
        Ok(raw_temp as f32 / 65536.0)
    }

    pub async fn pressure(&mut self) -> Result<f32> {
        // switch to standby & disable deep standby
        self.i2c
            .write(self.addr, &[ODR_CONFIG, 0x80])
            .await
            .map_err(|_| Error::WriteError)?;

        // enable pressure measurement
        self.i2c
            .write(self.addr, &[OSR_CONFIG, 0x40])
            .await
            .map_err(|_| Error::WriteError)?;

        // switch to forced & disable deep standby
        self.i2c
            .write(self.addr, &[ODR_CONFIG, 0x82])
            .await
            .map_err(|_| WriteError)?;

        // t_conv_p (hardcoded OSR=1x)
        self.delay.delay_us(1050).await;

        let mut press_buf = [0u8; 3];
        self.i2c
            .write_read(self.addr, &[PRESS_DATA_XLSB], &mut press_buf)
            .await
            .map_err(|_| Error::ReadError)?;
        let raw_press = LittleEndian::read_i24(&press_buf);
        Ok(raw_press as f32 / 64.0 / 100.0)
    }
}