Code

The main changes in the code are the image data and width. This will display the resistor symbol in the IEC-60617 style.

Generate project using esp-generate

We will enable async (Embassy) support for this project. To create the project, use the esp-generate command. Run the following:

esp-generate --chip esp32 oled-rawimg

This will open a screen asking you to select options.

Select the option "Enable unstable HAL features"
Then, select the option "Adds embassy framework support".

Just save it by pressing "s" in the keyboard.

Update Cargo.toml

ssd1306 = { git = "https://github.com/rust-embedded-community/ssd1306.git", rev = "f3a2f7aca421fbf3ddda45ecef0dfd1f0f12330e", features = [
    "async",
] }
embedded-graphics = "0.8.1"

#![allow(unused)]
fn main() {
// 31x7 pixel
#[rustfmt::skip]
const IMG_DATA: &[u8] = &[
    // 1st row
    0b00000001,0b11111111,0b11111111,0b00000000,
    // 2nd row
    0b00000001,0b11111111,0b11111111,0b00000000,
    //3rd row
    0b00000001,0b10000000,0b00000011,0b00000000,
    //4th row
    0b11111111,0b10000000,0b00000011,0b11111110,
    //5th row
    0b00000001,0b10000000,0b00000011,0b00000000,
    //6th row
    0b00000001,0b11111111,0b11111111,0b00000000,
    //7th row
    0b00000001,0b11111111,0b11111111,0b00000000,
];
}

We need to set the width to 31. We'll draw the image at the point (x=35, y=35), though there's no particular reason for choosing these coordinates. I just wanted to show something other than the point zero. Feel free to experiment with different values for the point and explore other options.

#![allow(unused)]
fn main() {
 let raw_image = ImageRaw::<BinaryColor>::new(IMG_DATA, 31);

let image = Image::new(&raw_image, Point::new(35, 35));
}

Clone the existing project

You can also clone (or refer) project I created and navigate to the oled-rawimg folder.

git clone https://github.com/ImplFerris/esp32-projects
cd esp32-projects/oled-rawimg

The full code

#![no_std]
#![no_main]

use defmt::info;
use embassy_executor::Spawner;
use embassy_time::{Duration, Timer};
use embedded_graphics::image::{Image, ImageRaw};
use embedded_graphics::pixelcolor::BinaryColor;
use embedded_graphics::prelude::Point;
use embedded_graphics::prelude::*;
use esp_hal::timer::timg::TimerGroup;
use esp_hal::{clock::CpuClock, time::Rate};
use esp_println as _;
use ssd1306::mode::DisplayConfigAsync;
use ssd1306::{
    prelude::DisplayRotation, size::DisplaySize128x64, I2CDisplayInterface, Ssd1306Async,
};

#[panic_handler]
fn panic(_: &core::panic::PanicInfo) -> ! {
    loop {}
}

// 31x7 pixel
#[rustfmt::skip]
const IMG_DATA: &[u8] = &[
    // 1st row
    0b00000001,0b11111111,0b11111111,0b00000000,
    // 2nd row
    0b00000001,0b11111111,0b11111111,0b00000000,
    //3rd row
    0b00000001,0b10000000,0b00000011,0b00000000,
    //4th row
    0b11111111,0b10000000,0b00000011,0b11111110,
    //5th row
    0b00000001,0b10000000,0b00000011,0b00000000,
    //6th row
    0b00000001,0b11111111,0b11111111,0b00000000,
    //7th row
    0b00000001,0b11111111,0b11111111,0b00000000,
];

#[esp_hal_embassy::main]
async fn main(_spawner: Spawner) {
    // generator version: 0.3.1

    let config = esp_hal::Config::default().with_cpu_clock(CpuClock::max());
    let peripherals = esp_hal::init(config);

    let timer0 = TimerGroup::new(peripherals.TIMG1);
    esp_hal_embassy::init(timer0.timer0);

    info!("Embassy initialized!");

    let i2c_bus = esp_hal::i2c::master::I2c::new(
        peripherals.I2C0,
        esp_hal::i2c::master::Config::default().with_frequency(Rate::from_khz(400)),
    )
    .unwrap()
    .with_scl(peripherals.GPIO18)
    .with_sda(peripherals.GPIO23)
    .into_async();

    let interface = I2CDisplayInterface::new(i2c_bus);

    // initialize the display
    let mut display = Ssd1306Async::new(interface, DisplaySize128x64, DisplayRotation::Rotate0)
        .into_buffered_graphics_mode();
    display.init().await.unwrap();

    let raw_image = ImageRaw::<BinaryColor>::new(IMG_DATA, 31);
    let image = Image::new(&raw_image, Point::new(35, 35));

    image.draw(&mut display).unwrap();
    display.flush().await.unwrap();

    loop {
        Timer::after(Duration::from_secs(1)).await;
    }
}