Errors using shared-bus with ESP32 (esp_idf_hal and bme280-rs)

[enelson1001]

I am trying to use shared-bus with ESP32 using esp_idf_hal and bme280-rs. If I don't use shared-bus I have no problems using bme280.

Code with problems

use esp_idf_hal::delay;
use esp_idf_hal::i2c;
use esp_idf_hal::prelude::*;
use esp_idf_sys as _; // If using the `binstart` feature of `esp-idf-sys`, always keep this module imported

use log::*;

use bme280::i2c::BME280;

fn main() {
    esp_idf_sys::link_patches();

    // Bind the log crate to the ESP Logging facilities
    esp_idf_svc::log::EspLogger::initialize_default();

    let peripherals = Peripherals::take().unwrap();
    let pins = peripherals.pins;

    // Create i2c interface on I2C0 with bus speed of 400kHz
    let i2c0 = peripherals.i2c0;
    let scl = pins.gpio22;
    let sda = pins.gpio21;
    let i2c_config = <i2c::config::MasterConfig as Default>::default().baudrate(400.kHz().into());

    let i2c_bus_0 = i2c::Master::<i2c::I2C0, _, _>::new(i2c0, i2c::MasterPins { sda, scl }, i2c_config).unwrap();

    let i2c_bus_manager = shared_bus::BusManagerSimple::new(i2c_bus_0);

    let mut i2c_bme280 = BME280::new_primary(i2c_bus_manager.acquire_i2c());  <-----ERROR HERE
    //let mut i2c_bme280 = BME280::new_primary(i2c_bus_0);  <---- This works fine no ERRORS when not using shared-bus

    let mut delay = delay::Ets;
    i2c_bme280.init(&mut delay).unwrap();    <---ERROR HERE

Errors

error[E0277]: the trait bound `I2cProxy<'_, NullMutex<esp_idf_hal::i2c::Master<I2C0, esp_idf_hal::gpio::Gpio21<esp_idf_hal::gpio::Unknown>, esp_idf_hal::gpio::Gpio22<esp_idf_hal::gpio::Unknown>>>>: embedded_hal::i2c::blocking::I2c` is not satisfied
  --> src/main.rs:46:46
   |
46 |     let mut i2c_bme280 = BME280::new_primary(i2c_bus_manager.acquire_i2c());
   |                          ------------------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `embedded_hal::i2c::blocking::I2c` is not implemented for `I2cProxy<'_, NullMutex<esp_idf_hal::i2c::Master<I2C0, esp_idf_hal::gpio::Gpio21<esp_idf_hal::gpio::Unknown>, esp_idf_hal::gpio::Gpio22<esp_idf_hal::gpio::Unknown>>>>`
   |                          |
   |                          required by a bound introduced by this call
   |
note: required by a bound in `bme280::i2c::BME280::<I2C>::new_primary`
  --> /home/ed/rust-crates/bme280-rs/src/i2c.rs:22:10
   |
22 |     I2C: I2c + ErrorType,
   |          ^^^ required by this bound in `bme280::i2c::BME280::<I2C>::new_primary`

error[E0599]: the method `init` exists for struct `bme280::i2c::BME280<I2cProxy<'_, NullMutex<esp_idf_hal::i2c::Master<I2C0, esp_idf_hal::gpio::Gpio21<esp_idf_hal::gpio::Unknown>, esp_idf_hal::gpio::Gpio22<esp_idf_hal::gpio::Unknown>>>>>`, but its trait bounds were not satisfied
  --> src/main.rs:49:16
   |
49 |     i2c_bme280.init(&mut delay).unwrap();
   |                ^^^^ method cannot be called on `bme280::i2c::BME280<I2cProxy<'_, NullMutex<esp_idf_hal::i2c::Master<I2C0, esp_idf_hal::gpio::Gpio21<esp_idf_hal::gpio::Unknown>, esp_idf_hal::gpio::Gpio22<esp_idf_hal::gpio::Unknown>>>>>` due to unsatisfied trait bounds
   |
  ::: /home/ed/.cargo/registry/src/github.com-1ecc6299db9ec823/shared-bus-0.2.3/src/proxies.rs:15:1
   |
15 | pub struct I2cProxy<'a, M> {
   | --------------------------
   | |
   | doesn't satisfy `_: embedded_hal::i2c::ErrorType`
   | doesn't satisfy `_: embedded_hal::i2c::blocking::I2c`
   |
   = note: the following trait bounds were not satisfied:
           `I2cProxy<'_, NullMutex<esp_idf_hal::i2c::Master<I2C0, esp_idf_hal::gpio::Gpio21<esp_idf_hal::gpio::Unknown>, esp_idf_hal::gpio::Gpio22<esp_idf_hal::gpio::Unknown>>>>: embedded_hal::i2c::blocking::I2c`
           `I2cProxy<'_, NullMutex<esp_idf_hal::i2c::Master<I2C0, esp_idf_hal::gpio::Gpio21<esp_idf_hal::gpio::Unknown>, esp_idf_hal::gpio::Gpio22<esp_idf_hal::gpio::Unknown>>>>: embedded_hal::i2c::ErrorType`

How can I make shared-bus work with esp_idf_hal and bme280-rs?

[Rahix]

The problem is here:

https://github.com/VersBinarii/bme280-rs/blob/1c8b587e83167bbf3d43ed9e5331f6846bf1927c/Cargo.toml#L16

bme280-rs is already using the embedded-hal 1.0 alpha version which is not yet supported here in shared-bus unfortunately (we're still on 0.2.x). This is in the works but I don't have anything ready yet...

[Rahix]

Pull-request #36 should help. I added support for the latest embedded-hal alpha's I2C traits over there. However, your dependencies are still on alpha.7 while the latest release is alpha.8 so you'll have to get them update first as well.

[Rahix]

Please let me know once you've tested this, I'll then merge the PR and publish a new release.

[enelson1001]

I have updated bme280-rs locally to use alpha.8. Does PR#36 support alpha.8 as esp_idf_hal requires alpha.8.

Thanks

[Rahix]

https://github.com/Rahix/shared-bus/blob/049f206fc6504337494aa3238465d1add6730f83/Cargo.toml#L27

[enelson1001]

This is what I did

1. Modified my project cargo.toml with the following.

   shared-bus = {git = "https://github.com/Rahix/shared-bus.git", version = "0.2.3", branch = "i2c-eh-alpha", features = ["eh-alpha"]}

   My code in main:

   let peripherals = Peripherals::take().unwrap();
   let pins = peripherals.pins;
   
   // Create i2c interface on I2C0 with bus speed of 400kHz
   let i2c0 = peripherals.i2c0;
   let scl = pins.gpio22;
   let sda = pins.gpio21;
   let i2c_config = <i2c::config::MasterConfig as Default>::default().baudrate(400.kHz().into());
   let i2c_bus_0 = i2c::Master::<i2c::I2C0, _, _>::new(i2c0, i2c::MasterPins { sda, scl }, i2c_config).unwrap();
   
   let i2c_bus_manager = shared_bus::BusManagerSimple::new(i2c_bus_0);
   let mut i2c_bme280 = BME280::new_primary(i2c_bus_manager.acquire_i2c());
   
   //let mut i2c_bme280 = BME280::new_primary(i2c_bus_0);
   let mut delay = delay::Ets;
   i2c_bme280.init(&mut delay).unwrap();
   
   thread::sleep(Duration::from_millis(5000));
   let mut count = 0;
   
   loop {
       let measurements = i2c_bme280.measure(&mut delay).unwrap();
       println!("Relative Humidity = {}%", measurements.humidity);
       println!("Temperature = {} deg C", measurements.temperature);
       println!("Pressure = {} pascals", measurements.pressure);
   
       count += 1;
   
       thread::sleep(Duration::from_millis(5000));
   
       if count == 5 {
           break;
       }
   }

   And now everything works (I haven't shared bus with SSD1306 display yet but will do shortly)

2. One question - We can't pass i2c_bus_manager as a reference correct? But we can make static?

thanks

[Rahix]

Great, thanks for testing! I'll get the PR merged.

One question - We can't pass i2c_bus_manager as a reference correct? But we can make static?

Please open a new issue and describe in more detail what you need.