Embassy-RP and RP2040-hal Compatibility??? - Embedded_Hal::PWM:SetDutyCycle Assistance

[Token-Thinker]

Hello All,

I'm building a project based on embedded-hal and embassy for various boards that does async operations. When doing research I noticed that the embassy-rp crate doesn't expose the channel functionality for setting the duty cycle using embedded-hal.

However rp2040-hal does expose that feature, but doesn't seem to have any ties to embassy, which leads to my issue/questions.

Is there a way for embassy-rp to exposes that or do I have to use rp2040-hal and if so will it work with embassy?

Any potential plans on merging the two?

[Token-Thinker]

from the rp-hal side they said they don't see any plans on merging the two.

thoughts from embassy maintainers? - https://github.com/rp-rs/rp-hal/issues/816

[lulf]

These are different HALs/projects with different goals, so it's fine for them to coexist. If there is some functionality you'd like to have exposed (I'm not sure what channel functionality relates to, PWM?), please give some more details and/or raise a PR.

[Token-Thinker]

@lulf

that makes sense as i was reading more into it.

essentially, i want to be able to expose the SetDutyCycle function using the embedded-hal crate as a source of truth for my project that will be using multiple mcus

the problem is in the implementation for PWM as it relates to embassy-rp2040, it directly slices and implements the "channel" control directly to the io vs letting you attach it like the rp-hal example below.

I hope that makes sense, thank you again for your response.

//! # PWM Blink Example
//.....omitting some setup configurations and imports 

#![no_std]
#![no_main]

use embedded_hal::pwm::SetDutyCycle;

fn main() -> ! {
    //.....omitting some setup configurations

    // Output channel B on PWM4 to GPIO 25
    let channel = &mut pwm.channel_b;
    channel.output_to(pins.gpio25);

    // Infinite loop, fading LED up and down
    loop {
        // Ramp brightness up
        for i in LOW..=HIGH {
            delay.delay_us(8);
            let _ = channel.set_duty_cycle(i); //<---------HERE
        }

        // Ramp brightness down
        for i in (LOW..=HIGH).rev() {
            delay.delay_us(8);
            let _ = channel.set_duty_cycle(i); //<----------HERE
        }

        delay.delay_ms(500);
    }
}

[decaday]

https://github.com/embassy-rs/embassy/blob/b31648f2e59a68748e1c0f1408d1658a2e5e6a08/examples/rp/src/bin/pwm.rs#L13 https://github.com/embassy-rs/embassy/blob/b31648f2e59a68748e1c0f1408d1658a2e5e6a08/examples/rp/src/bin/pwm.rs#L67-L69

[Token-Thinker]

https://github.com/embassy-rs/embassy/blob/b31648f2e59a68748e1c0f1408d1658a2e5e6a08/examples/rp/src/bin/pwm.rs#L13

https://github.com/embassy-rs/embassy/blob/b31648f2e59a68748e1c0f1408d1658a2e5e6a08/examples/rp/src/bin/pwm.rs#L67-L69

This could work! Thank you @decaday