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grodinomvertescher
grodino
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mvertescher
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Added example for LTDC screen controller
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‎Cargo.toml

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@@ -42,6 +42,7 @@ version = "1.0.2"
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cortex-m-semihosting = "0.3.3"
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panic-halt = "0.2.0"
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panic-semihosting = "0.5.2"
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embedded-graphics = "0.6.1"
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[features]
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device-selected = []
@@ -94,3 +95,7 @@ required-features = ["stm32f746", "rt"]
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[[example]]
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name = "timer"
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required-features = ["stm32f746", "rt"]
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[[example]]
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name = "stm32f7disco-screen"
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required-features = ["stm32f746", "rt"]

‎examples/stm32f7disco-screen/main.rs

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#![deny(warnings)]
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#![no_main]
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#![no_std]
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// Required
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extern crate panic_semihosting;
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use cortex_m_rt::entry;
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use embedded_graphics::{
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egcircle, egrectangle, egtext,
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fonts::Font6x8,
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pixelcolor::{Rgb565, RgbColor},
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prelude::*,
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primitive_style, text_style,
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};
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use stm32f7xx_hal::{
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device,
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gpio::Speed,
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ltdc::{Layer, PixelFormat},
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prelude::*,
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rcc::{HSEClock, HSEClockMode, Rcc},
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};
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mod screen;
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// DIMENSIONS
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const WIDTH: u16 = 480;
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const HEIGHT: u16 = 272;
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// Graphics framebuffer
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const FB_GRAPHICS_SIZE: usize = (WIDTH as usize) * (HEIGHT as usize);
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static mut FB_LAYER1: [u16; FB_GRAPHICS_SIZE] = [0; FB_GRAPHICS_SIZE];
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#[entry]
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fn main() -> ! {
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let perif = device::Peripherals::take().unwrap();
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let _cp = cortex_m::Peripherals::take().unwrap();
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let rcc_hal: Rcc = perif.RCC.constrain();
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// Set up pins
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let _gpioa = perif.GPIOA.split();
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let _gpiob = perif.GPIOB.split();
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let gpioe = perif.GPIOE.split();
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let gpiog = perif.GPIOG.split();
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let gpioh = perif.GPIOH.split();
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let gpioi = perif.GPIOI.split();
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let gpioj = perif.GPIOJ.split();
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let gpiok = perif.GPIOK.split();
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gpioe.pe4.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_B0
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gpiog.pg12.into_alternate_af9().set_speed(Speed::VeryHigh); // LTCD_B4
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gpioi.pi9.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_VSYNC
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gpioi.pi10.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_HSYNC
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gpioi.pi13.into_alternate_af14().set_speed(Speed::VeryHigh);
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gpioi.pi14.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_CLK
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gpioi.pi15.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R0
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gpioj.pj0.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R1
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gpioj.pj1.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R2
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gpioj.pj2.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R3
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gpioj.pj3.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R4
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gpioj.pj4.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R5
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gpioj.pj5.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R6
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gpioj.pj6.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_R7
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gpioj.pj7.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G0
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gpioj.pj8.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G1
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gpioj.pj9.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G2
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gpioj.pj10.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G3
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gpioj.pj11.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G4
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gpioj.pj13.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_B1
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gpioj.pj14.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_B2
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gpioj.pj15.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_B3
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gpiok.pk0.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G5
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gpiok.pk1.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G6
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gpiok.pk2.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_G7
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gpiok.pk4.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_B5
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gpiok.pk5.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_B6
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gpiok.pk6.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_D7
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gpiok.pk7.into_alternate_af14().set_speed(Speed::VeryHigh); // LTCD_E
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// HSE osc out in High Z
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gpioh.ph1.into_floating_input();
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let _clocks = rcc_hal
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.cfgr
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.hse(HSEClock::new(25.mhz(), HSEClockMode::Bypass))
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.sysclk(216.mhz())
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.hclk(216.mhz())
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.freeze();
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// LCD enable: set it low first to avoid LCD bleed while setting up timings
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let mut disp_on = gpioi.pi12.into_push_pull_output();
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disp_on.set_low().ok();
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// LCD backlight enable
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let mut backlight = gpiok.pk3.into_push_pull_output();
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backlight.set_high().ok();
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let mut display = screen::Stm32F7DiscoDisplay::new(perif.LTDC, perif.DMA2D);
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display
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.controller
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.config_layer(Layer::L1, unsafe { &mut FB_LAYER1 }, PixelFormat::RGB565);
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display.controller.enable_layer(Layer::L1);
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display.controller.reload();
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let display = &mut display;
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// LCD enable: activate LCD !
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disp_on.set_high().ok();
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let r = egrectangle!(
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top_left = (0, 0),
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bottom_right = (479, 271),
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style = primitive_style!(fill_color = Rgb565::new(0, 0b11110, 0b11011))
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);
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r.draw(display).ok();
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let c1 = egcircle!(
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center = (20, 20),
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radius = 8,
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style = primitive_style!(fill_color = Rgb565::new(0, 63, 0))
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);
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let c2 = egcircle!(
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center = (25, 20),
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radius = 8,
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style = primitive_style!(fill_color = Rgb565::new(31, 0, 0))
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);
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let t = egtext!(
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text = "Hello Rust!",
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top_left = (100, 100),
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style = text_style!(font = Font6x8, text_color = RgbColor::WHITE)
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);
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c1.draw(display).ok();
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c2.draw(display).ok();
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t.draw(display).ok();
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for i in 0..300 {
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let c1 = egcircle!(
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center = (20 + i, 20),
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radius = 8,
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style = primitive_style!(fill_color = RgbColor::GREEN)
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);
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c1.draw(display).ok();
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}
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loop {}
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}

‎examples/stm32f7disco-screen/screen.rs

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use embedded_graphics::{
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drawable::Pixel,
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geometry::Size,
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pixelcolor::{Rgb565, RgbColor},
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style::{PrimitiveStyle, Styled},
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DrawTarget,
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primitives
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};
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use stm32f7xx_hal::{
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device::{LTDC, DMA2D},
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ltdc::{DisplayConfig, Layer, DisplayController, SupportedWord, PixelFormat},
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rcc::{HSEClock, HSEClockMode},
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time::U32Ext,
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};
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/// STM32F7-DISCO board display
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pub const DISCO_SCREEN_CONFIG: DisplayConfig = DisplayConfig {
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active_width: 480,
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active_height: 272,
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h_back_porch: 13,
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h_front_porch: 30,
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h_sync: 30,
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v_back_porch: 2,
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v_front_porch: 2,
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v_sync: 10,
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frame_rate: 60,
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h_sync_pol: false,
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v_sync_pol: false,
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no_data_enable_pol: true,
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pixel_clock_pol: false,
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};
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pub struct Stm32F7DiscoDisplay<T: 'static + SupportedWord> {
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pub controller: DisplayController<T>,
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}
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impl<T: 'static + SupportedWord> Stm32F7DiscoDisplay<T> {
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pub fn new(ltdc: LTDC, dma2d: DMA2D) -> Stm32F7DiscoDisplay<T> {
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let controller = DisplayController::new(
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ltdc,
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dma2d,
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PixelFormat::RGB565,
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DISCO_SCREEN_CONFIG,
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Some(&HSEClock::new(25.mhz(), HSEClockMode::Bypass)),
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);
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Stm32F7DiscoDisplay {
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controller,
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}
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}
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}
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impl DrawTarget<Rgb565> for Stm32F7DiscoDisplay<u16> {
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type Error = core::convert::Infallible;
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/// Draw a `Pixel` that has a color defined
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fn draw_pixel(&mut self, pixel: Pixel<Rgb565>) -> Result<(), Self::Error> {
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let Pixel(coord, color) = pixel;
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let value: u16 = (color.b() as u16 & 0x1F)
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| ((color.g() as u16 & 0x3F) << 5)
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| ((color.r() as u16 & 0x1F) << 11);
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// TODO : draw pixel
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self.controller
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.draw_pixel(Layer::L1, coord.x as usize, coord.y as usize, value);
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Ok(())
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}
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/// Draw a hardware accelerated (by DMA2D) rectangle
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fn draw_rectangle(&mut self, item: &Styled<primitives::Rectangle, PrimitiveStyle<Rgb565>>) -> Result<(), Self::Error> {
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if item.style.stroke_color.is_none() {
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let top_left = (item.primitive.top_left.x as usize, item.primitive.top_left.y as usize);
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let bottom_right = (item.primitive.bottom_right.x as usize, item.primitive.bottom_right.y as usize);
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let color = match item.style.fill_color {
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Some(c) => {
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(c.b() as u32 & 0x1F) | ((c.g() as u32 & 0x3F) << 5) | ((c.r() as u32 & 0x1F) << 11)
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},
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None => 0u32
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};
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// Note(unsafe) because transfert might not be before an other write
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// to the buffer occurs. However, such Register -> Buffer transfert
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// is so fast that such issue does not occur
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// TODO : use safer DMA api when the embedde-hal DMA traits will be stabilised
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unsafe {self.controller.draw_rectangle(Layer::L1, top_left, bottom_right, color);}
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} else {
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self.draw_iter(item).unwrap();
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}
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Ok(())
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}
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/// Return the sise of the screen
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fn size(&self) -> Size {
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Size::new(480, 272)
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}
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}

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