Is there example for continuous ADC?

[phuongtran7]

Hi,

I'm trying to piece together and example on how to continuously read ADC. But I'm struggling at what to create for channels. This is currently what I have.

According to the Config.toml generate by the template project. I'm using esp-idf-svc version 0.49 and esp-idf-hal version 0.44.

use esp_idf_svc::hal::adc::AdcContConfig;
use esp_idf_svc::hal::adc::AdcContDriver;
use esp_idf_svc::hal::peripherals::Peripherals;
use std::thread;
use std::time::Duration;

fn main() -> anyhow::Result<()> {
    // It is necessary to call this function once. Otherwise some patches to the runtime
    // implemented by esp-idf-sys might not link properly. See https://github.com/esp-rs/esp-idf-template/issues/71
    esp_idf_svc::sys::link_patches();

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

    let peripherals = Peripherals::take()?;

    let config = AdcContConfig::default();

    // How do I create channels here?
    let adc = AdcContDriver::new(peripherals.adc1, &config, &channels)?;

    let mut data: [u8; 1024];

    loop {
        thread::sleep(Duration::from_millis(100));
        println!("ADC value: {}", adc.read_bytes(&mut data, 10)?);
    }
}

Thank you so much for your time and help.

[phuongtran7]

I finally got the program to compile and run on the ESP32-C3-DevKit-RUST-1. I don't know if this is correct as I don't have input yet unfortunately. But it seems to run just fine. I get 400 bytes every loop, consistent with the default config of 100 measurements.

use esp_idf_svc::hal::adc::{AdcContConfig, AdcContDriver};
use esp_idf_svc::hal::peripherals::Peripherals;
use esp_idf_svc::hal::units::Hertz;

fn main() -> anyhow::Result<()> {
    // It is necessary to call this function once. Otherwise some patches to the runtime
    // implemented by esp-idf-sys might not link properly. See https://github.com/esp-rs/esp-idf-template/issues/71
    esp_idf_svc::sys::link_patches();

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

    let peripherals = Peripherals::take()?;

    let config = AdcContConfig::default();

    let mut adc_1_channel_2 = peripherals.pins.gpio2;

    let mut adc = AdcContDriver::new(peripherals.adc1, &config, &mut adc_1_channel_2)?;

    adc.start()?;

    let mut data: [u8; 1024] = [0x0; 1024];

    loop {
        if let Ok(num_read) = adc.read_bytes(&mut data, 10) {
            println!("Read {} bytes.", num_read);
        }
    }
}

[phuongtran7]

My ESP32-C3-Lyra finally arrived so I was able to test the code. Below is the working code that uses the onboard mic. I was able to get the ADC reading, send it over the network and playback the audio with Rodio on desktop. I don't know if there is an example somewhere, but if needed I can try and create a PR for this example too.

use esp_idf_svc::hal::adc::{AdcContConfig, AdcContDriver, AdcMeasurement, Attenuated};
use esp_idf_svc::hal::modem::Modem;
use esp_idf_svc::hal::peripherals::Peripherals;
use esp_idf_svc::sys::EspError;
use log::{info, debug};

fn main() -> anyhow::Result<()> {
    // It is necessary to call this function once. Otherwise some patches to the runtime
    // implemented by esp-idf-sys might not link properly. See https://github.com/esp-rs/esp-idf-template/issues/71
    esp_idf_svc::sys::link_patches();

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

    let peripherals = Peripherals::take()?;

    let config = AdcContConfig::default();

    let adc_1_channel_0 = Attenuated::db11(peripherals.pins.gpio0);

    let mut adc = AdcContDriver::new(peripherals.adc1, &config, adc_1_channel_0)?;

    adc.start()?;

    // Default to just read 100 measurements per each read
    let mut samples: [AdcMeasurement; 100] = [Default::default(); 100];

    loop {
        if let Ok(num_read) = adc.read(&mut samples, 10) {
            debug!("Read {} measurement.", num_read);
            for index in 0..num_read {
                debug!("{}", samples[index].data());
            }
        }
    }
}

[Vollbrecht]

If you feel like working on a PR, i might suggest instead of creating a separate example for the continues ADC, to add a bit of docstrings to the modules and public API, as we currently lag it for the adc drivers. Since otherwise the continues Driver is similar to the oneshot one.

[phuongtran7]

Got it. I can definitely try and add some docstrings for the ADC module. I think that was problem when I first tried too.