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src/main.rs

@@ -46,59 +46,11 @@ async fn blink(pin: AnyPin, blink_delay: Duration) -> ! {
     }
 }
 
-#[embassy_executor::main]
+fn display_demo<D>(display: &mut D) -> Result<(), D::Error>
-async fn main(spawner: Spawner) {
+where
-    // Initialize the nRF
+    D: DrawTarget<Color = Rgb565>,
-    let p = embassy_nrf::init(Default::default());
+{
-
+    display.clear(Rgb565::CSS_DARK_OLIVE_GREEN)?;
-    // Spawn the blink task
-    spawner
-        .spawn(blink(p.P0_02.degrade(), Duration::from_millis(250)))
-        .expect("Failed to start blink task");
-
-    // Get the pins for SPI
-    let mosi = p.P0_13;
-    let miso = p.P0_12;
-    let sck = p.P0_30;
-    let cs_pin = p.P0_31;
-
-    // Create an SPI config
-    let mut spim_config = spim::Config::default();
-    spim_config.frequency = spim::Frequency::M8;
-
-    ///////////////////////////////////////////
-    // Create a new SPI interface on the nrf //
-    ///////////////////////////////////////////
-
-    // Grab the SPI Master mode peripheral form the nRF60
-    let spim = embassy_nrf::spim::Spim::new(p.SERIAL3, Irqs, sck, miso, mosi, spim_config);
-    // Use the SPI peripheral to create a shared bus
-    let spi_bus: Mutex<embassy_sync::blocking_mutex::raw::NoopRawMutex, _> =
-        Mutex::new(RefCell::new(spim));
-
-    // Setup the chip select as an output pin
-    let chip_select = Output::new(cs_pin, Level::Low, OutputDrive::Standard);
-    // Use the shared bus to create a SPI Device to use for the display
-    let spi_display = SpiDevice::new(&spi_bus, chip_select);
-
-    // Create a new SPI display interface
-    let direction_control = Output::new(p.P0_20, Level::High, OutputDrive::Standard);
-    let iface = SPIInterface::new(spi_display, direction_control);
-
-    // Create a new display
-    let display_reset = Output::new(p.P0_11, Level::High, OutputDrive::Standard);
-    let display_orientation = ili9341::Orientation::Landscape;
-    let display_size = ili9341::DisplaySize240x320;
-    let mut display = Ili9341::new(
-        iface,
-        display_reset,
-        &mut embassy_time::Delay,
-        display_orientation,
-        display_size,
-    )
-    .unwrap();
-
-    display.clear(Rgb565::CSS_DARK_OLIVE_GREEN).unwrap();
 
     // Create styles used by the drawing operations.
     let thin_stroke = PrimitiveStyle::with_stroke(Rgb565::WHITE, 1);
@@ -117,8 +69,7 @@ async fn main(spawner: Spawner) {
     display
         .bounding_box()
         .into_styled(border_stroke)
-        .draw(&mut display)
+        .draw(display)?;
-        .unwrap();
 
     // Draw a triangle.
     Triangle::new(
@@ -127,20 +78,17 @@ async fn main(spawner: Spawner) {
         Point::new(16 + 8, yoffset),
     )
     .into_styled(thin_stroke)
-    .draw(&mut display)
+    .draw(display)?;
-    .unwrap();
 
     // Draw a filled square
     Rectangle::new(Point::new(52, yoffset), Size::new(16, 16))
         .into_styled(fill)
-        .draw(&mut display)
+        .draw(display)?;
-        .unwrap();
 
     // Draw a circle with a 3px wide stroke.
     Circle::new(Point::new(88, yoffset), 17)
         .into_styled(thick_stroke)
-        .draw(&mut display)
+        .draw(display)?;
-        .unwrap();
 
     // Draw centered text.
     let text = "embedded-graphics";
@@ -150,17 +98,77 @@ async fn main(spawner: Spawner) {
         character_style,
         Alignment::Center,
     )
-    .draw(&mut display)
+    .draw(display)?;
+
+    Ok(())
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    // Initialize the nRF
+    let p = embassy_nrf::init(Default::default());
+
+    // Spawn the blink task
+    spawner
+        .spawn(blink(p.P0_02.degrade(), Duration::from_millis(250)))
+        .expect("Failed to start blink task");
+
+    ////////////////
+    // Setup pins //
+    ////////////////
+
+    let mosi = p.P0_13;
+    let miso = p.P0_12;
+    let sck = p.P0_30;
+    let cs_pin = p.P0_31;
+    let dc_pin = p.P0_20; // Data / Command pin for the display
+    let disp_rst_pin = p.P0_11;
+
+    // Initialize the CS, DC, and display reset pins as outputs
+    let chip_select = Output::new(cs_pin, Level::High, OutputDrive::Standard);
+    let direction_control = Output::new(dc_pin, Level::High, OutputDrive::Standard);
+    let display_reset = Output::new(disp_rst_pin, Level::High, OutputDrive::Standard);
+
+    ///////////////
+    // Setup SPI //
+    ///////////////
+
+    // Create an SPI config with the SPI frequency at 8MHz
+    let mut spim_config = spim::Config::default();
+    spim_config.frequency = spim::Frequency::M8;
+
+    // Grab the SPI Master peripheral form the nRF60
+    let spim = embassy_nrf::spim::Spim::new(p.SERIAL3, Irqs, sck, miso, mosi, spim_config);
+    // Use the SPI peripheral to create a shared SPI bus
+    let spi_bus: Mutex<embassy_sync::blocking_mutex::raw::NoopRawMutex, _> =
+        Mutex::new(RefCell::new(spim));
+
+    // Use the shared bus to create a SPI Device to use for the display
+    let spi_display = SpiDevice::new(&spi_bus, chip_select);
+    // Create a new SPI display interface
+    let iface = SPIInterface::new(spi_display, direction_control);
+
+    ////////////////////////
+    // Create the display //
+    ////////////////////////
+
+    // Some options for the display
+    let display_orientation = ili9341::Orientation::Landscape;
+    let display_size = ili9341::DisplaySize240x320;
+
+    // Create the display
+    let mut display = Ili9341::new(
+        iface,
+        display_reset,
+        &mut embassy_time::Delay,
+        display_orientation,
+        display_size,
+    )
     .unwrap();
 
-    let mut led = Output::new(p.P0_03, Level::Low, OutputDrive::Standard);
+    // Now loop, re-running the demo every second
-
     loop {
-        info!("Going high!");
+        display_demo(&mut display).expect("Failed to run display demo");
-        led.set_high();
+        Timer::after_secs(1).await;
-        Timer::after_millis(300).await;
-        info!("Going low!");
-        led.set_low();
-        Timer::after_millis(300).await;
     }
 }