Move examples to examples/

Also adds associated error variants `CannotPause` and `BadResponse`, an
associated helper function `Error::bad_response`, and the internal
helper function `transact_expecting` which shortens function bodies for
functions implementing simple handshake-like commands, like `mac
resume`.

CHANGELOG.md

@@ -5,8 +5,28 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## Unreleased - v0.2.0
 
+### Added
+- `Rn2903::system_version_bytes()`
+- `Rn2903::system_factory_reset()`
+- `Rn2903::system_module_reset()`
+- `Rn2903::mac_pause()` and `::mac_resume()`
+- `BadResponse` and `CannotPause` error variants
+- Examples directory with LED blinky and LoRa packet RX examples 
+
+### Changed
+
+### Deprecated
+
+### Removed
+- `main.rs` (moved to an example)
+
+### Fixed
+
+### Security
+
+## v0.1.0
 ### Added
 
 - GNU GPL v3 license

CONTRIBUTING.md

@@ -17,3 +17,13 @@ CHANGELOG.md.
 
 All method documentation is written in the present tense. For example, "Creates a new..."
 rather than "Create a new...".
+
+## Cutting a Release
+
+When cutting a release:
+
+- In CHANGELOG, rename the Unreleased section and add a new Unreleased section above it
+- Make a commit with only that change
+- Tag that commit like "v1.0.0"
+- Push main and the tag
+- `cargo publish`

examples/blinky.rs

@@ -0,0 +1,32 @@
+use rn2903::Rn2903;
+use std::env::args;
+use std::process::exit;
+use std::thread;
+use std::time::Duration;
+
+fn main() {
+    let args: Vec<_> = args().collect();
+    if args.len() <= 1 {
+        eprintln!("rn2903_blinky <serial port>");
+        eprintln!("\tReset the module and toggle pin 0b10 on and off.");
+        eprintln!("\tThis corresponds to the blue user LED on the LoStik.");
+        exit(1);
+    }
+
+    let mut txvr = Rn2903::new_at(&args[1]).expect("Could not open device. Error");
+    println!(
+        "Successfully connected. Version: {}",
+        txvr.system_version()
+            .expect("Could not read from device. Error:")
+    );
+
+    txvr.system_module_reset().unwrap();
+    txvr.transact(b"mac pause").unwrap();
+
+    loop {
+        txvr.transact(b"sys set pindig GPIO10 1").unwrap();
+        thread::sleep(Duration::from_millis(1000));
+        txvr.transact(b"sys set pindig GPIO10 0").unwrap();
+        thread::sleep(Duration::from_millis(1000));
+    }
+}

examples/lora_packet_rx.rs

@@ -0,0 +1,32 @@
+use rn2903::Rn2903;
+use std::env::args;
+use std::process::exit;
+use std::thread;
+use std::time::Duration;
+
+fn main() {
+    let args: Vec<_> = args().collect();
+    if args.len() <= 1 {
+        eprintln!("rn2903_lora_packet_rx <serial port>");
+        eprintln!("\tRecieve LoRa packets and print their corresponding hex values.");
+        exit(1);
+    }
+
+    let mut txvr = Rn2903::new_at(&args[1]).expect("Could not open device. Error");
+    println!(
+        "Successfully connected. Version: {}",
+        txvr.system_version()
+            .expect("Could not read from device. Error:")
+    );
+
+    txvr.mac_pause().unwrap();
+    txvr.transact(b"sys set pindig GPIO10 0").unwrap();
+    txvr.transact(b"radio rx 0").unwrap();
+    loop {
+        println!("{:?}", txvr.read_line().unwrap());
+        txvr.transact(b"sys set pindig GPIO10 1").unwrap();
+        thread::sleep(Duration::from_millis(100));
+        txvr.transact(b"sys set pindig GPIO10 0").unwrap();
+        txvr.transact(b"radio rx 0").unwrap();
+    }
+}

src/lib.rs

@@ -36,6 +36,19 @@ quick_error! {
             display("Could not verify version string. Expected a RN2903 firmware revision, got '{}'",
                 version)
         }
+        /// The device returned a response that doesn't make sense, given the command that
+        /// was issued.
+        BadResponse(expected: String, response: String) {
+            description("bad response from module")
+            display("Received a bad response from the module. Expected '{}', got '{}'.",
+                expected, response)
+        }
+        /// The device is operating in a mode which prevents MAC functionality from being
+        /// paused, but a pause was requested.
+        CannotPause {
+            description("the LoRaWAN MAC cannot be paused")
+            display("The LoRaWAN MAC cannot be paused right now, but a pause was requested.")
+        }
         /// The program has become disconnected from the RN2903 module due to an I/O
         /// error. It is possible the device was physically disconnected, or that the
         /// host operating system closed the serial port for some reason.
@@ -47,6 +60,12 @@ quick_error! {
     }
 }
 
+impl Error {
+    fn bad_response<S: Into<String>, T: Into<String>>(expected: S, response: T) -> Self {
+        Self::BadResponse(expected.into(), response.into())
+    }
+}
+
 /// Universal `Result` wrapper for the RN2903 interface.
 pub type Result<T> = std::result::Result<T, Error>;
 
@@ -133,9 +152,7 @@ pub struct Rn2903 {
 /// # Meta (type) Functions
 ///
 /// These functions deal with the type `Rn2903`, providing ways to create and manipulate
-/// the structure itself. Aside from performing validation of the device on the other side
+/// the structure itself.
-/// of the serial link, these functions do not communicate with the module.
-///
 /// ## Creating an `Rn2903`
 /// There are several  ways to create a `Rn2903` wrapper for an RN2903 serial connection.
 /// `::new_at()` is the recommended method, but `::new()` can be useful if the platform
@@ -220,6 +237,21 @@ impl Rn2903 {
         self.read_line()
     }
 
+    /// Convenience function for situations where only one response is expected according
+    /// to the module's documentation. Receiving another response means something wacky
+    /// is going on.
+    fn transact_expecting(&mut self, command: &[u8], expectation: &[u8]) -> Result<()> {
+        let bytes = self.transact(command)?;
+        if bytes != expectation {
+            Err(Error::bad_response(
+                bytes_to_string(expectation),
+                bytes_to_string(&bytes),
+            ))
+        } else {
+            Ok(())
+        }
+    }
+
     /// Writes the specified command to the module, adding a CRLF and flushing the buffer.
     ///
     /// Using [`::transact()`](#method.transact) is preferred.
@@ -274,7 +306,6 @@ impl Rn2903 {
 
         Ok(vec)
     }
-
 }
 
 /// # System API Functions
@@ -286,4 +317,55 @@ impl Rn2903 {
         let bytes = self.transact(b"sys get ver")?;
         Ok(bytes_to_string(&bytes))
     }
+
+    /// Queries the module for its firmware version information.
+    ///
+    /// As `::system_version()`, but returns bytes.
+    pub fn system_version_bytes(&mut self) -> Result<Vec<u8>> {
+        self.transact(b"sys get ver")
+    }
+
+    /// Resets the CPU on the connected module. State in memory is lost and the MAC
+    /// starts up upon reboot, automatically loading default LoRaWAN settings.
+    ///
+    /// Returns the system version, like `::system_version_bytes()`.
+    pub fn system_module_reset(&mut self) -> Result<Vec<u8>> {
+        self.transact(b"sys reset")
+    }
+
+    /// Performs a factory reset on the connected module. All EEPROM values are
+    /// restored to factory defaults. All LoRaWAN settings set by the user are lost.
+    ///
+    /// Returns the system version, like `::system_version_bytes()`.
+    pub fn system_factory_reset(&mut self) -> Result<Vec<u8>> {
+        self.transact(b"sys factoryRESET")
+    }
+}
+
+/// # MAC API Functions
+impl Rn2903 {
+    /// Pauses the LoRaWAN MAC functionality on the device, returning the number of
+    /// milliseconds for which the MAC can remain paused without affecting LoRaWAN
+    /// functionality.
+    ///
+    /// This command can fail with `CannotPause`, meaning the device is operating in a
+    /// mode (like LoRaWAN Class C mode) in which pausing the MAC for any period of time
+    /// would result in degraded service.
+    pub fn mac_pause(&mut self) -> Result<u32> {
+        let val = bytes_to_string(&self.transact(b"mac pause")?);
+        let ms: u32 = match val.parse() {
+            Ok(v) => v,
+            Err(_) => return Err(Error::bad_response("<integer>", val)),
+        };
+        if ms == 0 {
+            Err(Error::CannotPause)
+        } else {
+            Ok(ms)
+        }
+    }
+
+    /// Resumes LoRaWAN MAC functionality on the device after being paused.
+    pub fn mac_resume(&mut self) -> Result<()> {
+        self.transact_expecting(b"mac resume", b"ok")
+    }
 }

src/main.rs

@@ -1,17 +0,0 @@
-use rn2903::{Rn2903, bytes_to_string};
-use std::thread;
-use std::time::Duration;
-
-fn main() {
-    let mut txvr = Rn2903::new_at("/dev/ttyUSB0").expect("Could not open device. Error");
-    println!(
-        "Successfully connected. Version: {}",
-        txvr
-            .system_version()
-            .expect("Could not read from device. Error:")
-    );
-
-    dbg!(bytes_to_string(&txvr.transact(b"sys set pindig GPIO10 1").unwrap()));
-    thread::sleep(Duration::from_millis(200));
-    dbg!(bytes_to_string(&txvr.transact(b"sys set pindig GPIO10 0").unwrap()));
-}