stm32とSPI接続のSSD1331搭載有機ＥＬディスプレイでHello worldした。

#![no_main]
#![no_std]

#[allow(unused_extern_crates)]
extern crate panic_halt;

extern crate cortex_m;
extern crate cortex_m_rt;
extern crate cortex_m_semihosting;

extern crate embedded_hal;
extern crate stm32f30x_hal as hal;

extern crate embedded_graphics;
extern crate ssd1331;

use hal::delay::Delay;
use hal::gpio::gpioa::PA9;
use hal::gpio::gpiob::PB6;
use hal::gpio::gpioc::PC7;
use hal::gpio::{Output, PushPull};
use hal::prelude::*;
use hal::spi::Spi;
use hal::stm32f30x;

use cortex_m_rt::entry;
use embedded_graphics::{
    coord::Coord, fonts::Font6x8, pixelcolor::PixelColorU16, prelude::*, primitives::Circle,
    primitives::Line, primitives::Rect, primitives::Triangle,
};
use embedded_hal::digital::v2::OutputPin;
use ssd1331::{prelude::*, Builder};

#[entry]
fn main() -> ! {
    let cp = cortex_m::Peripherals::take().unwrap();
    let p = stm32f30x::Peripherals::take().unwrap();

    let mut flash = p.FLASH.constrain();
    let mut rcc = p.RCC.constrain();

    let clocks = rcc
        .cfgr
        .sysclk(64.mhz())
        .hclk(64.mhz())
        .pclk1(32.mhz())
        .pclk2(32.mhz())
        .freeze(&mut flash.acr);

    let mut delay = Delay::new(cp.SYST, clocks);

    let mut gpioa = p.GPIOA.split(&mut rcc.ahb);
    let mut gpiob = p.GPIOB.split(&mut rcc.ahb);
    let mut gpioc = p.GPIOC.split(&mut rcc.ahb);

    // OLED display SPI interface
    let sck = gpiob.pb13.into_af5(&mut gpiob.moder, &mut gpiob.afrh);
    let miso = gpiob.pb14.into_af5(&mut gpiob.moder, &mut gpiob.afrh);
    let mosi = gpiob.pb15.into_af5(&mut gpiob.moder, &mut gpiob.afrh);
    let spi = Spi::spi2(
        p.SPI2,
        (sck, miso, mosi),
        embedded_hal::spi::Mode {
            polarity: embedded_hal::spi::Polarity::IdleLow,
            phase: embedded_hal::spi::Phase::CaptureOnFirstTransition,
        },
        8.mhz(),
        clocks,
        &mut rcc.apb1,
    );

    // OLED display CS, D/C, RESET pins
    let mut oled_cs: PB6<Output<PushPull>> = gpiob
        .pb6
        .into_push_pull_output(&mut gpiob.moder, &mut gpiob.otyper);

    let oled_dc: PA9<Output<PushPull>> = gpioa
        .pa9
        .into_push_pull_output(&mut gpioa.moder, &mut gpioa.otyper);

    let mut oled_reset: PC7<Output<PushPull>> = gpioc
        .pc7
        .into_push_pull_output(&mut gpioc.moder, &mut gpioc.otyper);

    let mut display: GraphicsMode<_> = Builder::new().connect_spi(spi, oled_dc).into();

    // fall down to low the CS pin, activate the OLED display
    OutputPin::set_low(&mut oled_cs).unwrap();

    // initialize
    display.reset(&mut oled_reset, &mut delay);
    display.init().unwrap();

    let color = PixelColorU16(0xffff_u16);

    display.draw(
        Triangle::new(Coord::new(4, 20), Coord::new(12, 6), Coord::new(20, 20))
            .with_stroke(Some(color))
            .with_stroke_width(3)
            .into_iter(),
    );

    display.draw(
        Circle::new(Coord::new(30, 13), 7)
            .with_stroke(Some(color))
            .with_stroke_width(1)
            .into_iter(),
    );

    display.draw(
        Rect::new(Coord::new(42, 6), Coord::new(42 + 14, 6 + 14))
            .with_stroke(Some(color))
            .with_stroke_width(1)
            .into_iter(),
    );

    display.draw(
        Line::new(Coord::new(5, 25), Coord::new(60, 25))
            .with_stroke(Some(color))
            .with_stroke_width(10)
            .into_iter(),
    );

    display.draw(
        Font6x8::render_str("Hello World!")
            .with_stroke(Some(PixelColorU16(0xf800_u16)))
            .with_stroke_width(2)
            .translate(Coord::new(5, 30))
            .into_iter(),
    );

    display.draw(
        Font6x8::render_str("Hello Rust!")
            .with_stroke(Some(PixelColorU16(0x07e0_u16)))
            .with_stroke_width(2)
            .translate(Coord::new(5, 40))
            .into_iter(),
    );

    display.draw(
        Font6x8::render_str("Hello stm32!")
            .with_stroke(Some(PixelColorU16(0x001f_u16)))
            .with_stroke_width(2)
            .translate(Coord::new(5, 50))
            .into_iter(),
    );

    display.flush().unwrap();

    loop {}
}

$ cargo build --release  
$ cargo objcopy --release -- -O binary firmware.bin