jurajsadel/esp32c3-no-std-async-mqtt-demo

esp32c3-no-std-async-mqtt-demo

This is a simple demo that we will use on the upcoming Espressif DevCon23.

ESP32 variant: https://github.com/JurajSadel/esp32-no-std-async-mqtt-demo

ESP32S3 variant: https://github.com/JurajSadel/esp32s3-no-std-async-mqtt-demo

What it does

The application measures temperature (BMP180) and sends the results to MQTT via WiFi - everything is done asynchronously.

It's async no_std application that uses esp-hal, esp-wifi, and rust-mqtt crates. The main skeleton is made of embassy_dhcp and no_std_temperature_logger with a bunch of changes.

The first change is MQTT part added. We are using MQTTv5. As a broker, we usepublic-mqtt-broker and websocket-client to see the results.

As a next change, we had to make bmp180.rs async.

Build and run

You have to set the SSID and PASSWORD environment variables before building/running the program

cargo run --release

WARN: Be sure you are using release mode!

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

esp32c3-no-std-async-mqtt-demo's Issues

Switch to `#[embassy_executor::main(entry = "esp_riscv_rt::entry")]`

https://github.com/embassy-rs/embassy/blob/2c96fe917de6e0120053e80d8da5a98d0d0f35d0/embassy-macros/src/lib.rs#L111-L117

Instead of initializing the executor manually

ESP32 and ESP32-S3 example

It's very nice example for ESP32-C3.

Please, could you provide also the example for other most common ESP32 chips like plain old ESP32 and ESP32-S3 which are popular in some ePaper based boards?

Porvide instructions how to build

Current version of README does not contain instructions on how to build the project.
Build fails with:

error: environment variable `SSID` not defined at compile time
  --> src/main.rs:49:20
   |
49 | const SSID: &str = env!("SSID");
   |                    ^^^^^^^^^^^^
   |
   = help: use `std::env::var("SSID")` to read the variable at run time
   = note: this error originates in the macro `env` (in Nightly builds, run with -Z macro-backtrace for more info)

error: environment variable `PASSWORD` not defined at compile time
  --> src/main.rs:50:24
   |
50 | const PASSWORD: &str = env!("PASSWORD");
   |                        ^^^^^^^^^^^^^^^^
   |
   = help: use `std::env::var("PASSWORD")` to read the variable at run time
   = note: this error originates in the macro `env` (in Nightly builds, run with -Z macro-backtrace for more info)

Document how to increase the smoltcp DNS max server count

In some routers, the program crashes with the following panic:

I (270) boot: Disabling RNG early entropy source...
start connection task
Device capabilities: Ok(EnumSet(Client | AccessPoint))
Starting wifi
Wifi started!
About to connect...
Wifi connected!
Waiting to get IP address...
 
 
!! A panic occured in '/home/sergio/.cargo/registry/src/index.crates.io-6f17d22bba15001f/smoltcp-0.10.0/src/socket/dns.rs', at line 170, column 49
 
PanicInfo {
    payload: Any { .. },
    message: Some(
        called `Result::unwrap()` on an `Err` value: (),
    ),
    location: Location {
        file: "/home/sergio/.cargo/registry/src/index.crates.io-6f17d22bba15001f/smoltcp-0.10.0/src/socket/dns.rs",
        line: 170,
        col: 49,
    },
    can_unwind: true,
}

The solution was proposed by @MabezDev in #1 (comment):

For my router I also needed to bump the number of DNS servers smoltcp has capacity for with:

# .cargo/config.toml
[env]
SMOLTCP_DNS_MAX_SERVER_COUNT = "3"

Be warned that you have to do a clean build for those changes to take effect, see: rust-lang/cargo#10358