Add board support crate example.

src/bare-metal/microcontrollers/board-support.md

@@ -1 +1,17 @@
 # Board support crates
+
+Board support crates provide a further level of wrapping for a specific board for convenience.
+
+```rust,editable,compile_fail
+{{#include examples/src/bin/board_support.rs:Example}}
+```
+
+<details>
+
+ * In this case the board support crate is just providing more useful names, and a bit of
+   initialisation.
+ * The crate may also include drivers for some on-board devices outside of the microcontroller
+   itself.
+   * `microbit-v2` includes a simple driver for the LED matrix.
+
+</details>

src/bare-metal/microcontrollers/examples/Cargo.lock

@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "az"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7b7e4c2464d97fe331d41de9d5db0def0a96f4d823b8b32a2efd503578988973"
+
 [[package]]
 name = "bare-metal"
 version = "0.2.5"
@@ -11,6 +17,12 @@ dependencies = [
  "rustc_version",
 ]
 
+[[package]]
+name = "bare-metal"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8fe8f5a8a398345e52358e18ff07cc17a568fbca5c6f73873d3a62056309603"
+
 [[package]]
 name = "bitfield"
 version = "0.13.2"
@@ -35,19 +47,31 @@ dependencies = [
  "vcell",
 ]
 
+[[package]]
+name = "bytemuck"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c041d3eab048880cb0b86b256447da3f18859a163c3b8d8893f4e6368abe6393"
+
 [[package]]
 name = "cast"
 version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "37b2a672a2cb129a2e41c10b1224bb368f9f37a2b16b612598138befd7b37eb5"
 
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
 [[package]]
 name = "cortex-m"
 version = "0.7.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ec610d8f49840a5b376c69663b6369e71f4b34484b9b2eb29fb918d92516cb9"
 dependencies = [
- "bare-metal",
+ "bare-metal 0.2.5",
  "bitfield",
  "embedded-hal",
  "volatile-register",
@@ -73,6 +97,37 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "critical-section"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1706d332edc22aef4d9f23a6bb1c92360a403013c291af51247a737472dcae6"
+dependencies = [
+ "bare-metal 1.0.0",
+ "critical-section 1.1.1",
+]
+
+[[package]]
+name = "critical-section"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6548a0ad5d2549e111e1f6a11a6c2e2d00ce6a3dafe22948d67c2b443f775e52"
+
+[[package]]
+name = "crunchy"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a81dae078cea95a014a339291cec439d2f232ebe854a9d672b796c6afafa9b7"
+
+[[package]]
+name = "embedded-dma"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46c8c02e4347a0267ca60813c952017f4c5948c232474c6010a381a337f1bda4"
+dependencies = [
+ "stable_deref_trait",
+]
+
 [[package]]
 name = "embedded-dma"
 version = "0.2.0"
@@ -92,6 +147,24 @@ dependencies = [
  "void",
 ]
 
+[[package]]
+name = "embedded-storage"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "723dce4e9f25b6e6c5f35628e144794e5b459216ed7da97b7c4b66cdb3fa82ca"
+
+[[package]]
+name = "fixed"
+version = "1.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "55f3be4cf4fc227d3a63bb77512a2b7d364200b2a715f389155785c4d3345495"
+dependencies = [
+ "az",
+ "bytemuck",
+ "half",
+ "typenum",
+]
+
 [[package]]
 name = "gd32f1"
 version = "0.6.0"
@@ -113,13 +186,42 @@ dependencies = [
  "cast",
  "cortex-m",
  "cortex-m-rt",
- "embedded-dma",
+ "embedded-dma 0.2.0",
  "embedded-hal",
  "gd32f1",
  "nb 1.0.0",
  "void",
 ]
 
+[[package]]
+name = "half"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02b4af3693f1b705df946e9fe5631932443781d0aabb423b62fcd4d73f6d2fd0"
+dependencies = [
+ "crunchy",
+]
+
+[[package]]
+name = "microbit-common"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "45651d001be4281a6f4536c30f3d8522f231bc56fd58d5baf2c630f565d31256"
+dependencies = [
+ "embedded-hal",
+ "nrf52833-hal",
+ "tiny-led-matrix",
+]
+
+[[package]]
+name = "microbit-v2"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9895242259950730bc112623e4a2e37345dc51ddb5fc8878c110489260d84e7"
+dependencies = [
+ "microbit-common",
+]
+
 [[package]]
 name = "microcontroller-examples"
 version = "0.1.0"
@@ -128,6 +230,7 @@ dependencies = [
  "embedded-hal",
  "gd32f1",
  "gd32f1x0-hal",
+ "microbit-v2",
  "panic-halt",
 ]
 
@@ -146,6 +249,61 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "546c37ac5d9e56f55e73b677106873d9d9f5190605e41a856503623648488cae"
 
+[[package]]
+name = "nrf-hal-common"
+version = "0.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bd37b3fd039327b4005cc0d4ef20bce0a41bf521071774d5adb854e4b1230639"
+dependencies = [
+ "cast",
+ "cfg-if",
+ "cortex-m",
+ "embedded-dma 0.1.2",
+ "embedded-hal",
+ "embedded-storage",
+ "fixed",
+ "nb 1.0.0",
+ "nrf-usbd",
+ "nrf52833-pac",
+ "rand_core",
+ "void",
+]
+
+[[package]]
+name = "nrf-usbd"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "640e88d4c108743c667f03320d0c9ab24a20f183a7a1b18bde7891ee13fd92c5"
+dependencies = [
+ "bare-metal 1.0.0",
+ "cortex-m",
+ "critical-section 0.2.8",
+ "usb-device",
+ "vcell",
+]
+
+[[package]]
+name = "nrf52833-hal"
+version = "0.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87f76d269c9a239ffe24edaa5ee0972b102c04e898b464e3e9a12ab0eacd5f76"
+dependencies = [
+ "embedded-hal",
+ "nrf-hal-common",
+ "nrf52833-pac",
+]
+
+[[package]]
+name = "nrf52833-pac"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd69bdb25903e18e098c040ef31dc863814437af010dea8bd55aa31f686cb461"
+dependencies = [
+ "cortex-m",
+ "cortex-m-rt",
+ "vcell",
+]
+
 [[package]]
 name = "panic-halt"
 version = "0.2.0"
@@ -170,6 +328,12 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+
 [[package]]
 name = "rustc_version"
 version = "0.2.3"
@@ -211,12 +375,30 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "tiny-led-matrix"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a718c727b686154a7c7913f70d7ebc8956f701cbab466bc22035cb27f378882b"
+
+[[package]]
+name = "typenum"
+version = "1.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "497961ef93d974e23eb6f433eb5fe1b7930b659f06d12dec6fc44a8f554c0bba"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "84a22b9f218b40614adcb3f4ff08b703773ad44fa9423e4e0d346d5db86e4ebc"
 
+[[package]]
+name = "usb-device"
+version = "0.2.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f6cc3adc849b5292b4075fc0d5fdcf2f24866e88e336dd27a8943090a520508"
+
 [[package]]
 name = "vcell"
 version = "0.1.3"

src/bare-metal/microcontrollers/examples/Cargo.toml

@@ -10,8 +10,12 @@ cortex-m-rt = "0.7.0"
 embedded-hal = "0.2.6"
 gd32f1 = { version = "0.6.0", features = ["gd32f130", "rt"] }
 gd32f1x0-hal = { version = "0.7.1", features = ["rt", "gd32f130x8"] }
+microbit-v2 = "0.13.0"
 panic-halt = "0.2.0"
 
+[[bin]]
+name = "board_support"
+
 [[bin]]
 name = "pac"
 

src/bare-metal/microcontrollers/examples/src/bin/board_support.rs

@@ -0,0 +1,32 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// ANCHOR: Example
+#![no_main]
+#![no_std]
+
+extern crate panic_halt as _;
+
+use cortex_m_rt::entry;
+use microbit::{hal::prelude::*, Board};
+
+#[entry]
+fn main() -> ! {
+    let mut board = Board::take().unwrap();
+
+    board.display_pins.col1.set_low().unwrap();
+    board.display_pins.row1.set_high().unwrap();
+
+    loop {}
+}