start work on usart requests

src/b15f.rs

@@ -2,7 +2,10 @@
 //! interacting with the B15 on a high level. If you are writing code
 //! for the B15, this is the module you want to use.
 
-use std::process::Command;
+use std::{process::Command, time::Duration, fmt::{Debug, Display}, thread::sleep, error::Error};
+use serialport::SerialPort;
+
+use crate::request::Request;
 
 /// Hardcoded commit hash of the most recent firmware
 static COMMIT_HASH: &'static str = "bc459c80cec755d7df2c11a807d74e085cbed332";
@@ -23,9 +26,8 @@ macro_rules! log_end {
 }
 
 /// Structure representing the driver for the board 15
-#[derive(Debug)]
 pub struct B15F {
-	
+	usart: Box<dyn SerialPort>
 }
 
 impl B15F {
@@ -42,39 +44,50 @@ impl B15F {
 	/// 
 	/// let drv = B15F::new().unwrap();
 	/// ```
-	pub fn new() -> Result<B15F, &'static str> {
-		let drv = B15F {};
-		drv.init()
-	}
+	pub fn new() -> Result<B15F, String> {
+		let port = B15F::init_connection()?;
 
-	fn init(self) -> Result<B15F, &'static str> {
-		let devices = B15F::get_devices();
-
-		let device = match devices.first() {
-			Some(item) => item,
-			None => return Err("Failed to find adapter")
+		let mut drv =B15F {
+			usart: port
 		};
 
-		log!("Using adapter: {}", device);
-
-		log_start!("Establish connection with adapter");
-		todo!("Implement USART");
-		log_end!("Ok!");
-
 		log_start!("Testing connection");
-		todo!("Test connection");
+		for tries in 0..3 {
+			drv.discard();
+		}
 		log_end!("Ok!");
 
-		let info = self.get_board_info();
+		let info = drv.get_board_info();
 		log!("AVR firmware version: {} built at {} ({})", info[0], info[1], info[2]);
 
 		let avr_commit_hash = info[3];
 		if avr_commit_hash != COMMIT_HASH {
 			log!("Different commit hashes: {} vs {}", avr_commit_hash, COMMIT_HASH);
-			return Err("Versions incompatible. Please update the software!");
+			return Err("Versions incompatible. Please update the software!".into());
 		}
 
-		Ok(self)
+		Ok(drv)
+	}
+
+	fn init_connection() -> Result<Box<dyn SerialPort>, String> {
+		let devices = B15F::get_devices();
+
+		let device = match devices.first() {
+			Some(item) => item,
+			None => return Err("Failed to find adapter".into())
+		};
+
+		log!("Using adapter: {}", device);
+
+		log_start!("Establish connection with adapter");
+		
+		let port = serialport::new(device, 57_600)
+											.timeout(Duration::from_millis(1000))
+											.open()
+											.map_err(|err| err.to_string())?;
+		log_end!("Ok!");
+
+		Ok(port)
 	}
 
 	/// Yields information about the installed firmware on the B15
@@ -97,6 +110,18 @@ impl B15F {
 		todo!();
 	}
 
+	/// Clears data in the USART buffers on this device and on the B15
+	pub fn discard(&mut self) {
+		self.usart.clear(serialport::ClearBuffer::Output).unwrap();
+
+		for i in 0..16 {
+			self.usart.write(&Request::new().discard().done()[..]).unwrap();
+			sleep(Duration::from_millis(4));
+		}
+
+		self.usart.clear(serialport::ClearBuffer::Input).unwrap()
+	}
+
 	#[cfg(any(target_arch = "arm", target_arch = "aarch64"))]
 	fn get_devices() -> Vec<String> {
 		let output = Command::new("bash")
@@ -127,4 +152,12 @@ impl B15F {
 			.map(|item| item.into())
 			.collect()
 	}
+}
+
+impl Debug for B15F {
+	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+		writeln!(f, "Baudrate:  {}", self.usart.baud_rate().unwrap())?;
+		writeln!(f, "Data bits: {:?}", self.usart.data_bits().unwrap())?;
+		writeln!(f, "Parity:    {:?}", self.usart.parity().unwrap())
+	}
 }