Adds PPI support and example

Author: thalesfragoso

Cargo.toml

@@ -15,6 +15,7 @@ members = [
   "examples/twi-ssd1306",
   "examples/ecb-demo",
   "examples/ccm-demo",
+  "examples/ppi-demo",
 ]
 
 [profile.dev]

examples/ppi-demo/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "ppi-demo"
+version = "0.0.1"
+edition = "2018"
+authors = [ "Thales Fragoso <[email protected]>"]
+
+[dependencies]
+cortex-m = "0.6.2"
+cortex-m-rt = "0.6.12"
+rtt-target = {version = "0.2.0", features = ["cortex-m"] }
+
+nrf52810-hal = { path = "../../nrf52810-hal", features = ["rt"], optional = true }
+nrf52832-hal = { path = "../../nrf52832-hal", features = ["rt"], optional = true }
+nrf52840-hal = { path = "../../nrf52840-hal", features = ["rt"], optional = true }
+nrf52833-hal = { path = "../../nrf52833-hal", features = ["rt"], optional = true }
+nrf51-hal = { path = "../../nrf51-hal", features = ["rt"], optional = true}
+
+[[bin]]
+name = "ppi-demo"
+doc = false
+test = false
+
+[features]
+51 = ["nrf51-hal"]
+52810 = ["nrf52810-hal"]
+52832 = ["nrf52832-hal"]
+52840 = ["nrf52840-hal"]
+52833 = ["nrf52833-hal"]

examples/ppi-demo/Embed.toml

@@ -0,0 +1,46 @@
+[probe]
+# The index of the probe in the connected probe list.
+# probe_index = 0
+# The protocol to be used for communicating with the target.
+protocol = "Swd"
+# The speed in kHz of the data link to the target.
+# speed = 1337
+
+[flashing]
+# Whether or not the target should be flashed.
+enabled = true
+# Whether or not the target should be halted after flashing.
+halt_afterwards = false
+# Whether or not bytes erased but not rewritten with data from the ELF
+# should be restored with their contents before erasing.
+restore_unwritten_bytes = false
+# The path where an SVG of the assembled flash layout should be written to.
+# flash_layout_output_path = "out.svg"
+
+[general]
+# The chip name of the chip to be debugged.
+# chip = "nRF52832"
+# A list of chip descriptions to be loaded during runtime.
+chip_descriptions = []
+# The default log level to be used.
+log_level = "Warn"
+
+[rtt]
+# Whether or not an RTTUI should be opened after flashing.
+# This is exclusive and cannot be used with GDB at the moment.
+enabled = true
+# A list of channel associations to be displayed. If left empty, all channels are displayed.
+channels = [
+    # { up = 0, down = 0, name = "name" }
+]
+# The duration in ms for which the logger should retry to attach to RTT.
+timeout = 3000
+# Whether timestamps in the RTTUI are enabled
+show_timestamps = true
+
+[gdb]
+# Whether or not a GDB server should be opened after flashing.
+# This is exclusive and cannot be used with RTT at the moment.
+enabled = false
+# The connection string in host:port format wher the GDB server will open a socket.
+# gdb_connection_string

examples/ppi-demo/README.md

@@ -0,0 +1,19 @@
+# Programmable peripheral interconnect demo
+
+Choose the microcontroller with one of the following features:
+- 51
+- 52810
+- 52832
+- 52840
+
+Also, if using `cargo-embed`, change the `chip` and `protocol` fields in [Embed.toml](Embed.toml).
+
+This demo uses the [rtt-target](https://crates.io/crates/rtt-target) crate for communication.
+
+If using `cargo-embed`, just run
+
+```console
+$ cargo embed --release --features=52832 --target=thumbv7em-none-eabihf
+```
+
+Replace `52832` and `thumbv7em-none-eabihf` with the correct feature and target for your microcontroller.

examples/ppi-demo/src/main.rs

@@ -0,0 +1,106 @@
+#![no_std]
+#![no_main]
+
+#[cfg(not(any(
+    feature = "51",
+    feature = "52810",
+    feature = "52832",
+    feature = "52833",
+    feature = "52840"
+)))]
+compile_error!(
+    "This example requires one of the following device features enabled:
+        51
+        52810
+        52832
+        52833
+        52840"
+);
+
+// Import the right HAL/PAC crate, depending on the target chip
+#[cfg(feature = "51")]
+pub use nrf51_hal as hal;
+#[cfg(feature = "52810")]
+pub use nrf52810_hal as hal;
+#[cfg(feature = "52832")]
+pub use nrf52832_hal as hal;
+#[cfg(feature = "52833")]
+pub use nrf52833_hal as hal;
+#[cfg(feature = "52840")]
+pub use nrf52840_hal as hal;
+
+use {
+    core::{
+        cell::RefCell,
+        panic::PanicInfo,
+        sync::atomic::{compiler_fence, Ordering},
+    },
+    cortex_m::interrupt::Mutex,
+    cortex_m_rt::entry,
+    hal::{
+        pac::{interrupt, Interrupt, RADIO},
+        ppi,
+        prelude::*,
+        timer::Timer,
+        Clocks,
+    },
+    rtt_target::{rprintln, rtt_init_print},
+};
+
+static RADIO_REGS: Mutex<RefCell<Option<RADIO>>> = Mutex::new(RefCell::new(None));
+
+#[entry]
+fn main() -> ! {
+    let p = hal::pac::Peripherals::take().unwrap();
+
+    let _clocks = Clocks::new(p.CLOCK).enable_ext_hfosc();
+    rtt_init_print!();
+
+    let ppi_channels = ppi::Parts::new(p.PPI);
+    let mut channel0 = ppi_channels.ppi0;
+
+    channel0.set_task_endpoint(&p.RADIO.tasks_disable as *const _ as u32);
+    channel0.set_event_endpoint(&p.TIMER0.events_compare[0] as *const _ as u32);
+    channel0.enable();
+
+    let radio = p.RADIO;
+    radio.intenset.write(|w| w.disabled().set());
+    cortex_m::interrupt::free(|cs| RADIO_REGS.borrow(cs).replace(Some(radio)));
+    // NOTE(unsafe) There isn't any abstraction depending on this interrupt being masked
+    unsafe {
+        cortex_m::peripheral::NVIC::unmask(Interrupt::RADIO);
+    }
+
+    let mut timer = Timer::one_shot(p.TIMER0);
+    timer.start(0xFFFFu32);
+
+    loop {
+        // Prevent empty loop optimizations
+        compiler_fence(Ordering::SeqCst);
+    }
+}
+
+#[interrupt]
+fn RADIO() {
+    cortex_m::interrupt::free(|cs| {
+        if let Some(regs) = RADIO_REGS.borrow(cs).borrow_mut().as_mut() {
+            if regs.events_disabled.read().bits() == 1 {
+                rprintln!("We hit the RADIO disabled interrupt");
+
+                // Clear the disabled flag
+                // NOTE(unsafe) 0 is a valid value to write to this register
+                regs.events_disabled.write(|w| unsafe { w.bits(0) });
+            }
+        }
+    });
+}
+
+#[inline(never)]
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    cortex_m::interrupt::disable();
+    rprintln!("{}", info);
+    loop {
+        compiler_fence(Ordering::SeqCst);
+    }
+}

nrf-hal-common/src/lib.rs

@@ -31,6 +31,8 @@ pub mod delay;
 pub mod ecb;
 pub mod gpio;
 #[cfg(not(feature = "9160"))]
+pub mod ppi;
+#[cfg(not(feature = "9160"))]
 pub mod rng;
 pub mod rtc;
 #[cfg(not(feature = "51"))]
@@ -58,6 +60,8 @@ pub mod prelude {
     pub use crate::hal::digital::v2::*;
     pub use crate::hal::prelude::*;
 
+    #[cfg(not(feature = "9160"))]
+    pub use crate::ppi::{ConfigurablePpi, Ppi};
     pub use crate::time::U32Ext;
 }