Merge pull request #731 from stm32-rs/ltdc

port ltdc from f7xx-hal

Author: therealprof

CHANGELOG.md

@@ -9,13 +9,16 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
- - `i2c_scanner` example
+ - `i2c_scanner` example [#758]
+ - port LTDC implementation and example from stm32f7xx-hal [#731]
 
 ### Changed
 
  - Use `stm32f4-staging` until `stm32f4` is released [#706]
 
 [#706]: https://github.com/stm32-rs/stm32f4xx-hal/pull/706
+[#731]: https://github.com/stm32-rs/stm32f4xx-hal/pull/731
+[#758]: https://github.com/stm32-rs/stm32f4xx-hal/pull/758
 
 ## [v0.21.0] - 2024-05-30
 

Cargo.toml

@@ -61,6 +61,8 @@ embedded-storage = "0.3"
 vcell = "0.1.3"
 document-features = "0.2"
 
+micromath = { version = "2.1.0", optional = true }
+
 [dependencies.stm32f4]
 package = "stm32f4-staging"
 version = "0.16.0"
@@ -320,6 +322,7 @@ gpio-f427 = [
     "can2",
     "dac",
     "dcmi",
+    "dma2d",
     "eth",
     "i2c3",
     "ltdc",
@@ -406,6 +409,7 @@ gpio-f469 = [
     "can1",
     "can2",
     "dac",
+    "dma2d",
     "dcmi",
     "dsihost",
     "eth",
@@ -494,6 +498,7 @@ dac = []
 dcmi = []
 dfsdm1 = ["dfsdm"]
 dfsdm2 = ["dfsdm"]
+dma2d = []
 dsihost = []
 eth = []
 fmc = []
@@ -508,7 +513,7 @@ gpioj = []
 gpiok = []
 i2c3 = []
 lptim1 = []
-ltdc = []
+ltdc = ["dep:micromath"]
 quadspi = []
 otg-fs = []
 otg-hs = []
@@ -725,6 +730,10 @@ required-features = ["tim2"]                   # stm32f411
 name = "stopwatch-with-ssd1306-and-interrupts-and-dma-i2c"
 required-features = ["tim2", "stm32f411"]                  # stm32f411
 
+[[example]]
+name = "ltdc-screen"
+required-features = ["stm32f429"]
+
 [[example]]
 name = "timer-periph"
 required-features = []

examples/ltdc-screen/main.rs

@@ -0,0 +1,129 @@
+#![no_main]
+#![no_std]
+
+// Required
+extern crate panic_semihosting;
+
+use cortex_m_rt::entry;
+use embedded_graphics::{
+    mono_font::{ascii::FONT_6X9, MonoTextStyle},
+    pixelcolor::{Rgb565, RgbColor},
+    prelude::*,
+    primitives::{Circle, PrimitiveStyle, Rectangle},
+    text::Text,
+};
+
+use stm32f4xx_hal::{
+    ltdc::{BluePins, GreenPins, Layer, LtdcPins, PixelFormat, RedPins},
+    pac,
+    prelude::*,
+    rcc::Rcc,
+};
+
+mod screen;
+
+// DIMENSIONS
+const WIDTH: u16 = 480;
+const HEIGHT: u16 = 272;
+
+// Graphics framebuffer
+const FB_GRAPHICS_SIZE: usize = (WIDTH as usize) * (HEIGHT as usize);
+static mut FB_LAYER1: [u16; FB_GRAPHICS_SIZE] = [0; FB_GRAPHICS_SIZE];
+
+#[entry]
+fn main() -> ! {
+    let perif = pac::Peripherals::take().unwrap();
+    let _cp = cortex_m::Peripherals::take().unwrap();
+
+    let rcc_hal: Rcc = perif.RCC.constrain();
+
+    // Set up pins
+    let _gpioa = perif.GPIOA.split();
+    let _gpiob = perif.GPIOB.split();
+    let gpioe = perif.GPIOE.split();
+    let gpiog = perif.GPIOG.split();
+    let gpioh = perif.GPIOH.split();
+    let gpioi = perif.GPIOI.split();
+    let gpioj = perif.GPIOJ.split();
+    let gpiok = perif.GPIOK.split();
+
+    let pins = LtdcPins::new(
+        RedPins::new(
+            gpioi.pi15, gpioj.pj0, gpioj.pj1, gpioj.pj2, gpioj.pj3, gpioj.pj4, gpioj.pj5, gpioj.pj6,
+        ),
+        GreenPins::new(
+            gpioj.pj7, gpioj.pj8, gpioj.pj9, gpioj.pj10, gpioj.pj11, gpiok.pk0, gpiok.pk1,
+            gpiok.pk2,
+        ),
+        BluePins::new(
+            gpioe.pe4, gpioj.pj13, gpioj.pj14, gpioj.pj15, gpiog.pg12, gpiok.pk4, gpiok.pk5,
+            gpiok.pk6,
+        ),
+        gpioi.pi10,
+        gpioi.pi9,
+        gpiok.pk7,
+        gpioi.pi14,
+    );
+
+    // HSE osc out in High Z
+    gpioh.ph1.into_floating_input();
+    let _clocks = rcc_hal
+        .cfgr
+        .use_hse(25.MHz())
+        .bypass_hse_oscillator()
+        .sysclk(216.MHz())
+        .hclk(216.MHz())
+        .freeze();
+
+    // LCD enable: set it low first to avoid LCD bleed while setting up timings
+    let mut disp_on = gpioi.pi12.into_push_pull_output();
+    disp_on.set_low();
+
+    // LCD backlight enable
+    let mut backlight = gpiok.pk3.into_push_pull_output();
+    backlight.set_high();
+
+    let mut display = screen::Stm32F7DiscoDisplay::new(perif.LTDC, perif.DMA2D, pins);
+    display
+        .controller
+        .config_layer(Layer::L1, unsafe { &mut FB_LAYER1 }, PixelFormat::RGB565);
+
+    display.controller.enable_layer(Layer::L1);
+    display.controller.reload();
+
+    let display = &mut display;
+
+    // LCD enable: activate LCD !
+    disp_on.set_high();
+
+    Rectangle::new(Point::new(0, 0), Size::new(479, 271))
+        .into_styled(PrimitiveStyle::with_fill(Rgb565::new(0, 0b11110, 0b11011)))
+        .draw(display)
+        .ok();
+
+    let c1 = Circle::new(Point::new(20, 20), 2 * 8)
+        .into_styled(PrimitiveStyle::with_fill(Rgb565::new(0, 63, 0)));
+
+    let c2 = Circle::new(Point::new(25, 20), 2 * 8)
+        .into_styled(PrimitiveStyle::with_fill(Rgb565::new(31, 0, 0)));
+
+    let t = Text::new(
+        "Hello Rust!",
+        Point::new(100, 100),
+        MonoTextStyle::new(&FONT_6X9, RgbColor::WHITE),
+    );
+
+    c1.draw(display).ok();
+    c2.draw(display).ok();
+    t.draw(display).ok();
+
+    for i in 0..300 {
+        Circle::new(Point::new(20 + i, 20), 2 * 8)
+            .into_styled(PrimitiveStyle::with_fill(RgbColor::GREEN))
+            .draw(display)
+            .ok();
+    }
+
+    #[allow(clippy::empty_loop)]
+    loop {}
+}

examples/ltdc-screen/screen.rs

@@ -0,0 +1,78 @@
+use embedded_graphics::{
+    pixelcolor::{Rgb565, RgbColor},
+    prelude::{DrawTarget, OriginDimensions, Pixel, Size},
+};
+
+use stm32f4xx_hal::{
+    ltdc::{DisplayConfig, DisplayController, Layer, LtdcPins, PixelFormat, SupportedWord},
+    pac::{DMA2D, LTDC},
+    prelude::*,
+};
+
+/// STM32F7-DISCO board display
+pub const DISCO_SCREEN_CONFIG: DisplayConfig = DisplayConfig {
+    active_width: 480,
+    active_height: 272,
+    h_back_porch: 13,
+    h_front_porch: 30,
+    h_sync: 41,
+    v_back_porch: 2,
+    v_front_porch: 2,
+    v_sync: 10,
+    frame_rate: 60,
+    h_sync_pol: false,
+    v_sync_pol: false,
+    no_data_enable_pol: false,
+    pixel_clock_pol: false,
+};
+
+pub struct Stm32F7DiscoDisplay<T: 'static + SupportedWord> {
+    pub controller: DisplayController<T>,
+}
+
+impl<T: 'static + SupportedWord> Stm32F7DiscoDisplay<T> {
+    pub fn new(ltdc: LTDC, dma2d: DMA2D, pins: LtdcPins) -> Stm32F7DiscoDisplay<T> {
+        let controller = DisplayController::new(
+            ltdc,
+            dma2d,
+            pins,
+            PixelFormat::RGB565,
+            DISCO_SCREEN_CONFIG,
+            Some(25.MHz()),
+        );
+
+        Stm32F7DiscoDisplay { controller }
+    }
+}
+
+impl DrawTarget for Stm32F7DiscoDisplay<u16> {
+    type Color = Rgb565;
+    type Error = core::convert::Infallible;
+
+    fn draw_iter<I>(&mut self, pixels: I) -> Result<(), Self::Error>
+    where
+        I: IntoIterator<Item = Pixel<Self::Color>>,
+    {
+        for Pixel(coord, color) in pixels.into_iter() {
+            // Check if the pixel coordinates are out of bounds (negative or greater than
+            // (480,272)). `DrawTarget` implementation are required to discard any out of bounds
+            // pixels without returning an error or causing a panic.
+            if let (x @ 0..=479, y @ 0..=271) = coord.into() {
+                let value: u16 = (color.b() as u16 & 0x1F)
+                    | ((color.g() as u16 & 0x3F) << 5)
+                    | ((color.r() as u16 & 0x1F) << 11);
+
+                self.controller
+                    .draw_pixel(Layer::L1, x as usize, y as usize, value);
+            }
+        }
+
+        Ok(())
+    }
+}
+
+impl OriginDimensions for Stm32F7DiscoDisplay<u16> {
+    fn size(&self) -> Size {
+        Size::new(480, 272)
+    }
+}

src/lib.rs

@@ -109,6 +109,8 @@ pub mod dwt;
 pub mod flash;
 #[cfg(all(feature = "fsmc_lcd", any(feature = "fmc", feature = "fsmc")))]
 pub mod fsmc_lcd;
+#[cfg(all(feature = "dma2d", feature = "ltdc"))]
+pub mod ltdc;
 pub mod prelude;
 pub mod qei;
 #[cfg(feature = "quadspi")]