[WIP] Add super simple blinky example for Arduino Nano Every

This is all a big jumbled mess and in no way "production ready".

Clock/delay seems to be wrong, at least the blinky blinks way too
slow...

Author: Rahix

Cargo.toml

@@ -29,6 +29,7 @@ members = [
     "examples/arduino-mega2560",
     "examples/arduino-mega1280",
     "examples/arduino-nano",
+    "examples/arduino-nano-every",
     "examples/arduino-uno",
     "examples/atmega2560",
     "examples/nano168",

examples/arduino-nano-every/.cargo/config.toml

@@ -0,0 +1,5 @@
+[build]
+target = "../../avr-specs/avr-atmega4809.json"
+
+[unstable]
+build-std = ["core"]

examples/arduino-nano-every/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "arduino-nano-every-examples"
+version = "0.0.0"
+authors = ["Rahix <[email protected]>"]
+edition = "2018"
+publish = false
+
+[dependencies]
+panic-halt = "0.2.0"
+ufmt = "0.1.0"
+nb = "0.1.2"
+embedded-hal = "0.2.3"
+
+[dependencies.atxmega-hal]
+path = "../../mcu/atxmega-hal/"
+features = ["atmega4809", "rt"]

examples/arduino-nano-every/src/bin/every-blink.rs

@@ -0,0 +1,34 @@
+#![no_std]
+#![no_main]
+
+// Proof of concept, all hacked together right now...
+//
+// Compile with the dirty avr-atmega4809.json target (which actually uses atxmega32a4 ...).
+//
+// Flashing works using the following command, based on the Arduino stuff (not verified anything
+// else yet):
+//
+// stty -F /dev/ttyACM0 hup 1200 && \
+//      echo 1>/dev/ttyACM0 && \
+//      ~/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino17/bin/avrdude \
+//          -C${HOME}/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino17/etc/avrdude.conf \
+//          -v -patmega4809 -cjtag2updi -P/dev/ttyACM0 -b115200 -e -D \
+//          -Uflash:w:../../target/avr-atmega4809/release/every-blink.elf:e
+
+use panic_halt as _;
+
+use embedded_hal::blocking::delay::DelayMs;
+
+#[atxmega_hal::entry]
+fn main() -> ! {
+    let dp = atxmega_hal::Peripherals::take().unwrap();
+
+    let mut led = dp.pins.pe2.into_output();
+
+    let mut delay = atxmega_hal::delay::Delay::<atxmega_hal::clock::MHz16>::new();
+
+    loop {
+        led.toggle();
+        delay.delay_ms(100u16);
+    }
+}