test the nrf52840 HAL using defmt-test

this commit adds tests that exercise the GPIO API
3 connections are required:
- P0.03 <-> GND
- P0.04 <-> VDD
- P0.28 <-> P0.29
the first two are used to test the Input API against reference voltages
the short-circuit connection is used to test the Input and Output API using the input API that was
previously tested

Author: japaric

.cargo/config

@@ -1,8 +1,2 @@
 [alias]
 xtask = "run -p xtask --"
-
-[target.'cfg(all(target_arch = "arm", target_os = "none"))']
-runner = 'arm-none-eabi-gdb'
-rustflags = [
-    "-C", "link-arg=-Tlink.x",
-]

Cargo.toml

@@ -6,9 +6,11 @@ members = [
   "nrf52832-hal",
   "nrf52833-hal",
   "nrf52840-hal",
+  "nrf52840-hal-tests",
   "nrf9160-hal",
   "examples/*",
 ]
+exclude = ["examples/.cargo"]
 
 [profile.dev]
 incremental = false

examples/.cargo/config

@@ -0,0 +1,5 @@
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+runner = 'arm-none-eabi-gdb'
+rustflags = [
+    "-C", "link-arg=-Tlink.x",
+]

nrf52840-hal-tests/.cargo/config.toml

@@ -0,0 +1,11 @@
+[target.thumbv7em-none-eabihf]
+runner = "probe-run --chip nRF52840_xxAA --probe 1366:1015"
+rustflags = [
+  "-C", "link-arg=--nmagic",
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tdefmt.x",
+  "-C", "linker=flip-link",
+]
+
+[build]
+target = "thumbv7em-none-eabihf"

nrf52840-hal-tests/.gitignore

@@ -0,0 +1 @@
+target

nrf52840-hal-tests/Cargo.toml

@@ -0,0 +1,44 @@
+[package]
+edition = "2018"
+name = "nrf52840-hal-tests"
+publish = false
+version = "0.0.0"
+
+[[test]]
+name = "gpio-input"
+harness = false
+
+[[test]]
+name = "gpio-output-push-pull"
+harness = false
+
+[[test]]
+name = "gpio-output-open-drain"
+harness = false
+
+[[test]]
+name = "gpio-pull"
+harness = false
+
+[[test]]
+name = "serial"
+harness = false
+
+[dev-dependencies]
+defmt = "0.1.3"
+defmt-rtt = "0.1.0"
+defmt-test = "0.1.1"
+nrf52840-hal = { path = "../nrf52840-hal" }
+panic-probe = { version = "0.1.0", features = ["print-defmt"] }
+
+[features]
+# enable all defmt logging levels
+default = ["defmt-trace"]
+
+# do not modify these features
+defmt-default = []
+defmt-trace = []
+defmt-debug = []
+defmt-info = []
+defmt-warn = []
+defmt-error = []

nrf52840-hal-tests/README.md

@@ -0,0 +1,12 @@
+# nRF52840 HAL tests
+
+Run `cargo test -p nrf52840-hal-tests` to test the HAL on a nRF52840.
+
+The crate assumes that you'll test the HAL on a nRF52840 Development Kit.
+If you wish to use a different development board you'll need to update the flags passed to `probe-run` in `.cargo/config.toml`.
+
+The following wiring is required:
+
+- P0.03 <-> GND
+- P0.04 <-> VDD
+- P0.28 <-> P0.29

nrf52840-hal-tests/tests/gpio-input.rs

@@ -0,0 +1,51 @@
+// Required connections:
+//
+// - P0.03 <-> GND
+// - P0.04 <-> VDD
+
+#![deny(warnings)]
+#![no_std]
+#![no_main]
+
+use defmt_rtt as _;
+use nrf52840_hal as _;
+use panic_probe as _;
+
+use nrf52840_hal::gpio::{Floating, Input, Pin};
+
+struct State {
+    input_ground: Pin<Input<Floating>>,
+    input_vdd: Pin<Input<Floating>>,
+}
+
+#[defmt_test::tests]
+mod tests {
+    use defmt::{assert, unwrap};
+    use nrf52840_hal::{gpio::p0, pac, prelude::*};
+
+    use super::State;
+
+    #[init]
+    fn init() -> State {
+        let p = unwrap!(pac::Peripherals::take());
+        let port0 = p0::Parts::new(p.P0);
+
+        let input_ground = port0.p0_03.into_floating_input().degrade();
+        let input_vdd = port0.p0_04.into_floating_input().degrade();
+
+        State {
+            input_ground,
+            input_vdd,
+        }
+    }
+
+    #[test]
+    fn ground_is_low(state: &mut State) {
+        assert!(state.input_ground.is_low().unwrap());
+    }
+
+    #[test]
+    fn vdd_is_high(state: &mut State) {
+        assert!(state.input_vdd.is_high().unwrap());
+    }
+}

nrf52840-hal-tests/tests/gpio-output-open-drain.rs

@@ -0,0 +1,62 @@
+// Required connections:
+//
+// - P0.28 <-> P0.29
+
+#![deny(warnings)]
+#![no_std]
+#![no_main]
+
+use defmt_rtt as _;
+use nrf52840_hal as _;
+use panic_probe as _;
+
+use nrf52840_hal::gpio::{Floating, Input, OpenDrain, Output, Pin};
+
+struct State {
+    input_pin: Pin<Input<Floating>>,
+    output_pin: Pin<Output<OpenDrain>>,
+}
+
+#[defmt_test::tests]
+mod tests {
+    use defmt::{assert, unwrap};
+    use nrf52840_hal::{
+        gpio::{p0, Level, OpenDrainConfig},
+        pac,
+        prelude::*,
+    };
+
+    use super::State;
+
+    #[init]
+    fn init() -> State {
+        let p = unwrap!(pac::Peripherals::take());
+        let port0 = p0::Parts::new(p.P0);
+
+        let input_pin = port0.p0_28.into_floating_input().degrade();
+        let output_pin = port0
+            .p0_29
+            .into_open_drain_output(OpenDrainConfig::Standard0Disconnect1, Level::High)
+            .degrade();
+
+        State {
+            input_pin,
+            output_pin,
+        }
+    }
+
+    #[test]
+    fn set_low_is_low(state: &mut State) {
+        state.output_pin.set_low().unwrap();
+        assert!(state.input_pin.is_low().unwrap());
+    }
+
+    // with the current API we cannot test this w/o an _external_ pull-up
+    /* 
+    #[test]
+    fn set_high_is_high(state: &mut State) {
+        state.output_pin.set_high().unwrap();
+        assert!(state.input_pin.is_high().unwrap());
+    }
+    */
+}

nrf52840-hal-tests/tests/gpio-output-push-pull.rs

@@ -0,0 +1,56 @@
+// Required connections:
+//
+// - P0.28 <-> P0.29
+
+#![deny(warnings)]
+#![no_std]
+#![no_main]
+
+use defmt_rtt as _;
+use nrf52840_hal as _;
+use panic_probe as _;
+
+use nrf52840_hal::gpio::{Floating, Input, Output, Pin, PushPull};
+
+struct State {
+    input_pin: Pin<Input<Floating>>,
+    output_pin: Pin<Output<PushPull>>,
+}
+
+#[defmt_test::tests]
+mod tests {
+    use defmt::{assert, unwrap};
+    use nrf52840_hal::{
+        gpio::{p0, Level},
+        pac,
+        prelude::*,
+    };
+
+    use super::State;
+
+    #[init]
+    fn init() -> State {
+        let p = unwrap!(pac::Peripherals::take());
+        let port0 = p0::Parts::new(p.P0);
+
+        let input_pin = port0.p0_28.into_floating_input().degrade();
+        let output_pin = port0.p0_29.into_push_pull_output(Level::High).degrade();
+
+        State {
+            input_pin,
+            output_pin,
+        }
+    }
+
+    #[test]
+    fn set_low_is_low(state: &mut State) {
+        state.output_pin.set_low().unwrap();
+        assert!(state.input_pin.is_low().unwrap());
+    }
+
+    #[test]
+    fn set_high_is_high(state: &mut State) {
+        state.output_pin.set_high().unwrap();
+        assert!(state.input_pin.is_high().unwrap());
+    }
+}