Merge pull request embassy-rs#3057 from dvdsk/docs-net-size

Document w5500 State and add w5500 example for stmf4

Author: Dirbaio

embassy-net-wiznet/src/lib.rs

@@ -17,12 +17,22 @@ use embedded_hal_async::spi::SpiDevice;
 use crate::chip::Chip;
 use crate::device::WiznetDevice;
 
+// If you change this update the docs of State
 const MTU: usize = 1514;
 
 /// Type alias for the embassy-net driver.
 pub type Device<'d> = embassy_net_driver_channel::Device<'d, MTU>;
 
 /// Internal state for the embassy-net integration.
+///
+/// The two generic arguments `N_RX` and `N_TX` set the size of the receive and
+/// send packet queue. With a the ethernet MTU of _1514_ this takes up `N_RX +
+/// NTX * 1514` bytes. While setting these both to 1 is the minimum this might
+/// hurt performance as a packet can not be received while processing another.
+///
+/// # Warning
+/// On devices with a small amount of ram (think ~64k) watch out with the size
+/// of there parameters. They will quickly use too much RAM.
 pub struct State<const N_RX: usize, const N_TX: usize> {
     ch_state: ch::State<MTU, N_RX, N_TX>,
 }

examples/stm32f4/Cargo.toml

@@ -12,6 +12,7 @@ embassy-executor = { version = "0.5.0", path = "../../embassy-executor", feature
 embassy-time = { version = "0.3.1", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-usb = { version = "0.2.0", path = "../../embassy-usb", features = ["defmt" ] }
 embassy-net = { version = "0.4.0", path = "../../embassy-net", features = ["defmt", "tcp", "dhcpv4", "medium-ethernet", ] }
+embassy-net-wiznet = { version = "0.1.0", path = "../../embassy-net-wiznet", features = ["defmt"] }
 embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
 
 defmt = "0.3"
@@ -20,6 +21,7 @@ defmt-rtt = "0.4"
 cortex-m = { version = "0.7.6", features = ["inline-asm", "critical-section-single-core"] }
 cortex-m-rt = "0.7.0"
 embedded-hal = "0.2.6"
+embedded-hal-bus = { version = "0.2", features = ["async"] }
 embedded-io = { version = "0.6.0" }
 embedded-io-async = { version = "0.6.1" }
 panic-probe = { version = "0.3", features = ["print-defmt"] }

examples/stm32f4/src/bin/eth_w5500.rs

@@ -0,0 +1,138 @@
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_net::tcp::TcpSocket;
+use embassy_net::{Ipv4Address, Stack, StackResources};
+use embassy_net_wiznet::chip::W5500;
+use embassy_net_wiznet::{Device, Runner, State};
+use embassy_stm32::exti::ExtiInput;
+use embassy_stm32::gpio::{Level, Output, Pull, Speed};
+use embassy_stm32::mode::Async;
+use embassy_stm32::rng::Rng;
+use embassy_stm32::spi::Spi;
+use embassy_stm32::time::Hertz;
+use embassy_stm32::{bind_interrupts, peripherals, rng, spi, Config};
+use embassy_time::{Delay, Timer};
+use embedded_hal_bus::spi::ExclusiveDevice;
+use embedded_io_async::Write;
+use static_cell::StaticCell;
+use {defmt_rtt as _, panic_probe as _};
+
+bind_interrupts!(struct Irqs {
+    HASH_RNG => rng::InterruptHandler<peripherals::RNG>;
+});
+
+type EthernetSPI = ExclusiveDevice<Spi<'static, Async>, Output<'static>, Delay>;
+#[embassy_executor::task]
+async fn ethernet_task(runner: Runner<'static, W5500, EthernetSPI, ExtiInput<'static>, Output<'static>>) -> ! {
+    runner.run().await
+}
+
+#[embassy_executor::task]
+async fn net_task(stack: &'static Stack<Device<'static>>) -> ! {
+    stack.run().await
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) -> ! {
+    let mut config = Config::default();
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.hse = Some(Hse {
+            freq: Hertz(8_000_000),
+            mode: HseMode::Bypass,
+        });
+        config.rcc.pll_src = PllSource::HSE;
+        config.rcc.pll = Some(Pll {
+            prediv: PllPreDiv::DIV4,
+            mul: PllMul::MUL180,
+            divp: Some(PllPDiv::DIV2), // 8mhz / 4 * 180 / 2 = 180Mhz.
+            divq: None,
+            divr: None,
+        });
+        config.rcc.ahb_pre = AHBPrescaler::DIV1;
+        config.rcc.apb1_pre = APBPrescaler::DIV4;
+        config.rcc.apb2_pre = APBPrescaler::DIV2;
+        config.rcc.sys = Sysclk::PLL1_P;
+    }
+    let p = embassy_stm32::init(config);
+
+    info!("Hello World!");
+
+    // Generate random seed
+    let mut rng = Rng::new(p.RNG, Irqs);
+    let mut seed = [0; 8];
+    unwrap!(rng.async_fill_bytes(&mut seed).await);
+    let seed = u64::from_le_bytes(seed);
+
+    let mut spi_cfg = spi::Config::default();
+    spi_cfg.frequency = Hertz(50_000_000); // up to 50m works
+    let (miso, mosi, clk) = (p.PA6, p.PA7, p.PA5);
+    let spi = Spi::new(p.SPI1, clk, mosi, miso, p.DMA2_CH3, p.DMA2_CH0, spi_cfg);
+    let cs = Output::new(p.PA4, Level::High, Speed::VeryHigh);
+    let spi = unwrap!(ExclusiveDevice::new(spi, cs, Delay));
+
+    let w5500_int = ExtiInput::new(p.PB0, p.EXTI0, Pull::Up);
+    let w5500_reset = Output::new(p.PB1, Level::High, Speed::VeryHigh);
+
+    let mac_addr = [0x02, 234, 3, 4, 82, 231];
+    static STATE: StaticCell<State<2, 2>> = StaticCell::new();
+    let state = STATE.init(State::<2, 2>::new());
+    let (device, runner) = embassy_net_wiznet::new(mac_addr, state, spi, w5500_int, w5500_reset).await;
+    unwrap!(spawner.spawn(ethernet_task(runner)));
+
+    let config = embassy_net::Config::dhcpv4(Default::default());
+    //let config = embassy_net::Config::ipv4_static(embassy_net::StaticConfigV4 {
+    //    address: Ipv4Cidr::new(Ipv4Address::new(10, 42, 0, 61), 24),
+    //    dns_servers: Vec::new(),
+    //    gateway: Some(Ipv4Address::new(10, 42, 0, 1)),
+    //});
+
+    static STACK: StaticCell<Stack<Device>> = StaticCell::new();
+    static RESOURCES: StaticCell<StackResources<2>> = StaticCell::new();
+    let stack = &*STACK.init(Stack::new(
+        device,
+        config,
+        RESOURCES.init(StackResources::<2>::new()),
+        seed,
+    ));
+
+    // Launch network task
+    unwrap!(spawner.spawn(net_task(stack)));
+
+    // Ensure DHCP configuration is up before trying connect
+    stack.wait_config_up().await;
+
+    info!("Network task initialized");
+
+    // Then we can use it!
+    let mut rx_buffer = [0; 1024];
+    let mut tx_buffer = [0; 1024];
+
+    loop {
+        let mut socket = TcpSocket::new(stack, &mut rx_buffer, &mut tx_buffer);
+
+        socket.set_timeout(Some(embassy_time::Duration::from_secs(10)));
+
+        let remote_endpoint = (Ipv4Address::new(10, 42, 0, 1), 8000);
+        info!("connecting...");
+        let r = socket.connect(remote_endpoint).await;
+        if let Err(e) = r {
+            info!("connect error: {:?}", e);
+            Timer::after_secs(1).await;
+            continue;
+        }
+        info!("connected!");
+        let buf = [0; 1024];
+        loop {
+            let r = socket.write_all(&buf).await;
+            if let Err(e) = r {
+                info!("write error: {:?}", e);
+                break;
+            }
+            Timer::after_secs(1).await;
+        }
+    }
+}