Add DCMI example.

1 files changed, 339 insertions, 0 deletions

diff --git a/examples/stm32h7/src/bin/camera.rs b/examples/stm32h7/src/bin/camera.rs
new file mode 100644
index 000000000..2fa742b83
--- /dev/null
+++ b/examples/stm32h7/src/bin/camera.rs
@@ -0,0 +1,339 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy_stm32::dcmi::*;
+use embassy_stm32::gpio::{Level, NoPin, Output, Speed};
+use embassy_stm32::i2c::I2c;
+use embassy_stm32::interrupt;
+use embassy_stm32::rcc::{Mco, Mco1Source, McoClock};
+use embassy_stm32::time::U32Ext;
+use embassy_stm32::Peripherals;
+use embedded_hal::digital::v2::OutputPin;
+
+use defmt_rtt as _; // global logger
+use panic_probe as _;
+
+use core::sync::atomic::{AtomicUsize, Ordering};
+use embassy_stm32::Config;
+
+defmt::timestamp! {"{=u64}", {
+        static COUNT: AtomicUsize = AtomicUsize::new(0);
+        // NOTE(no-CAS) `timestamps` runs with interrupts disabled
+        let n = COUNT.load(Ordering::Relaxed);
+        COUNT.store(n + 1, Ordering::Relaxed);
+        n as u64
+    }
+}
+
+#[allow(unused)]
+pub fn config() -> Config {
+    let mut config = Config::default();
+    config.rcc.sys_ck = Some(400.mhz().into());
+    config.rcc.hclk = Some(400.mhz().into());
+    config.rcc.pll1.q_ck = Some(100.mhz().into());
+    config.rcc.enable_dma1 = true;
+    config.rcc.enable_dma2 = true;
+    config.rcc.pclk1 = Some(100.mhz().into());
+    config.rcc.pclk2 = Some(100.mhz().into());
+    config.rcc.pclk3 = Some(100.mhz().into());
+    config.rcc.pclk4 = Some(100.mhz().into());
+    config
+}
+
+use ov7725::*;
+
+const WIDTH: usize = 100;
+const HEIGHT: usize = 100;
+
+static mut FRAME: [u32; WIDTH * HEIGHT / 2] = [0u32; WIDTH * HEIGHT / 2];
+
+#[embassy::main(config = "config()")]
+async fn main(_spawner: Spawner, p: Peripherals) {
+    defmt::info!("Hello World!");
+    let mco = Mco::new(p.MCO1, p.PA8, Mco1Source::Hsi, McoClock::Divided(3));
+
+    let mut led = Output::new(p.PE3, Level::High, Speed::Low);
+    let i2c_irq = interrupt::take!(I2C1_EV);
+    let cam_i2c = I2c::new(
+        p.I2C1,
+        p.PB8,
+        p.PB9,
+        i2c_irq,
+        p.DMA1_CH1,
+        p.DMA1_CH2,
+        100u32.khz(),
+    );
+
+    let mut camera = Ov7725::new(cam_i2c, mco);
+
+    defmt::unwrap!(camera.init().await);
+
+    let manufacturer_id = defmt::unwrap!(camera.read_manufacturer_id().await);
+    let camera_id = defmt::unwrap!(camera.read_product_id().await);
+
+    defmt::info!(
+        "manufacturer: 0x{:x}, pid: 0x{:x}",
+        manufacturer_id,
+        camera_id
+    );
+
+    let dcmi_irq = interrupt::take!(DCMI);
+    let mut dcmi = Dcmi::new(
+        p.DCMI,
+        p.DMA1_CH0,
+        VSyncDataInvalidLevel::High,
+        HSyncDataInvalidLevel::Low,
+        PixelClockPolarity::RisingEdge,
+        false,
+        dcmi_irq,
+        p.PC6,
+        p.PC7,
+        p.PE0,
+        p.PE1,
+        p.PE4,
+        p.PD3,
+        p.PE5,
+        p.PE6,
+        NoPin,
+        NoPin,
+        NoPin,
+        NoPin,
+        NoPin,
+        NoPin,
+        p.PB7,
+        p.PA4,
+        p.PA6,
+    );
+
+    defmt::info!("attempting capture");
+    defmt::unwrap!(dcmi.capture(unsafe { &mut FRAME }).await);
+
+    defmt::info!("captured frame: {:x}", unsafe { &FRAME });
+
+    defmt::info!("main loop running");
+    loop {
+        defmt::info!("high");
+        defmt::unwrap!(led.set_high());
+        Timer::after(Duration::from_millis(500)).await;
+
+        defmt::info!("low");
+        defmt::unwrap!(led.set_low());
+        Timer::after(Duration::from_millis(500)).await;
+    }
+}
+
+mod ov7725 {
+    use core::marker::PhantomData;
+
+    use defmt::Format;
+    use embassy::time::{Duration, Timer};
+    use embassy_stm32::rcc::{Mco, McoInstance};
+    use embassy_traits::i2c::I2c;
+
+    #[repr(u8)]
+    pub enum RgbFormat {
+        Gbr422 = 0,
+        RGB565 = 1,
+        RGB555 = 2,
+        RGB444 = 3,
+    }
+    pub enum PixelFormat {
+        Yuv,
+        ProcessedRawBayer,
+        Rgb(RgbFormat),
+        RawBayer,
+    }
+
+    impl From<PixelFormat> for u8 {
+        fn from(raw: PixelFormat) -> Self {
+            match raw {
+                PixelFormat::Yuv => 0,
+                PixelFormat::ProcessedRawBayer => 1,
+                PixelFormat::Rgb(mode) => 2 | ((mode as u8) << 2),
+                PixelFormat::RawBayer => 3,
+            }
+        }
+    }
+
+    #[derive(Clone, Copy)]
+    #[repr(u8)]
+    #[allow(unused)]
+    pub enum Register {
+        Gain = 0x00,
+        Blue = 0x01,
+        Red = 0x02,
+        Green = 0x03,
+        BAvg = 0x05,
+        GAvg = 0x06,
+        RAvg = 0x07,
+        Aech = 0x08,
+        Com2 = 0x09,
+        PId = 0x0a,
+        Ver = 0x0b,
+        Com3 = 0x0c,
+        Com4 = 0x0d,
+        Com5 = 0x0e,
+        Com6 = 0x0f,
+        Aec = 0x10,
+        ClkRc = 0x11,
+        Com7 = 0x12,
+        Com8 = 0x13,
+        Com9 = 0x14,
+        Com10 = 0x15,
+        Reg16 = 0x16,
+        HStart = 0x17,
+        HSize = 0x18,
+        VStart = 0x19,
+        VSize = 0x1a,
+        PShift = 0x1b,
+        MidH = 0x1c,
+        MidL = 0x1d,
+        Laec = 0x1f,
+        Com11 = 0x20,
+        BdBase = 0x22,
+        BdMStep = 0x23,
+        Aew = 0x24,
+        Aeb = 0x25,
+        Vpt = 0x26,
+        Reg28 = 0x28,
+        HOutSize = 0x29,
+        EXHCH = 0x2a,
+        EXHCL = 0x2b,
+        VOutSize = 0x2c,
+        Advfl = 0x2d,
+        Advfh = 0x2e,
+        Yave = 0x2f,
+        LumHTh = 0x30,
+        LumLTh = 0x31,
+        HRef = 0x32,
+        DspCtrl4 = 0x67,
+        DspAuto = 0xac,
+    }
+
+    const CAM_ADDR: u8 = 0x21;
+
+    #[derive(Format)]
+    pub enum Error<I2cError: Format> {
+        I2c(I2cError),
+    }
+
+    pub struct Ov7725<'d, Bus: I2c> {
+        phantom: PhantomData<&'d ()>,
+        bus: Bus,
+    }
+
+    impl<'d, Bus> Ov7725<'d, Bus>
+    where
+        Bus: I2c,
+        Bus::Error: Format,
+    {
+        pub fn new<T>(bus: Bus, _mco: Mco<T>) -> Self
+        where
+            T: McoInstance,
+        {
+            Self {
+                phantom: PhantomData,
+                bus,
+            }
+        }
+
+        pub async fn init(&mut self) -> Result<(), Error<Bus::Error>> {
+            Timer::after(Duration::from_millis(500)).await;
+            self.reset_regs().await?;
+            Timer::after(Duration::from_millis(500)).await;
+            self.set_pixformat().await?;
+            self.set_resolution().await?;
+            Ok(())
+        }
+
+        pub async fn read_manufacturer_id(&mut self) -> Result<u16, Error<Bus::Error>> {
+            Ok(u16::from_le_bytes([
+                self.read(Register::MidL).await?,
+                self.read(Register::MidH).await?,
+            ]))
+        }
+
+        pub async fn read_product_id(&mut self) -> Result<u16, Error<Bus::Error>> {
+            Ok(u16::from_le_bytes([
+                self.read(Register::Ver).await?,
+                self.read(Register::PId).await?,
+            ]))
+        }
+
+        async fn reset_regs(&mut self) -> Result<(), Error<Bus::Error>> {
+            self.write(Register::Com7, 0x80).await
+        }
+
+        async fn set_pixformat(&mut self) -> Result<(), Error<Bus::Error>> {
+            self.write(Register::DspCtrl4, 0).await?;
+            let mut com7 = self.read(Register::Com7).await?;
+            com7 |= u8::from(PixelFormat::Rgb(RgbFormat::RGB565));
+            self.write(Register::Com7, com7).await?;
+            Ok(())
+        }
+
+        async fn set_resolution(&mut self) -> Result<(), Error<Bus::Error>> {
+            let horizontal: u16 = super::WIDTH as u16;
+            let vertical: u16 = super::HEIGHT as u16;
+
+            let h_high = (horizontal >> 2) as u8;
+            let v_high = (vertical >> 1) as u8;
+            let h_low = (horizontal & 0x03) as u8;
+            let v_low = (vertical & 0x01) as u8;
+
+            self.write(Register::HOutSize, h_high).await?;
+            self.write(Register::VOutSize, v_high).await?;
+            self.write(Register::EXHCH, h_low | (v_low << 2)).await?;
+
+            self.write(Register::Com3, 0xd1).await?;
+
+            let com3 = self.read(Register::Com3).await?;
+            let vflip = com3 & 0x80 > 0;
+
+            self.modify(Register::HRef, |reg| {
+                reg & 0xbf | if vflip { 0x40 } else { 0x40 }
+            })
+            .await?;
+
+            if horizontal <= 320 || vertical <= 240 {
+                self.write(Register::HStart, 0x3f).await?;
+                self.write(Register::HSize, 0x50).await?;
+                self.write(Register::VStart, 0x02).await?; // TODO vflip is subtracted in the original code
+                self.write(Register::VSize, 0x78).await?;
+            } else {
+                defmt::panic!("VGA resolutions not yet supported.");
+            }
+
+            Ok(())
+        }
+
+        async fn read(&mut self, register: Register) -> Result<u8, Error<Bus::Error>> {
+            let mut buffer = [0u8; 1];
+            self.bus
+                .write_read(CAM_ADDR, &[register as u8], &mut buffer[..1])
+                .await
+                .map_err(Error::I2c)?;
+            Ok(buffer[0])
+        }
+
+        async fn write(&mut self, register: Register, value: u8) -> Result<(), Error<Bus::Error>> {
+            self.bus
+                .write(CAM_ADDR, &[register as u8, value])
+                .await
+                .map_err(Error::I2c)
+        }
+
+        async fn modify<F: FnOnce(u8) -> u8>(
+            &mut self,
+            register: Register,
+            f: F,
+        ) -> Result<(), Error<Bus::Error>> {
+            let value = self.read(register).await?;
+            let value = f(value);
+            self.write(register, value).await
+        }
+    }
+}