Improved chances for successful sync

src/target.rs

@@ -37,7 +37,6 @@ impl PhysicalTarget {
 	}
 
 	pub fn resync_target(&mut self) -> Result<(), Error> {
-		self.port.discard_buffers()?;
 		self.port.set_dtr(true)?;
 		self.port.set_rts(true)?;
 		std::thread::sleep(Duration::from_millis(10));
@@ -45,6 +44,8 @@ impl PhysicalTarget {
 		std::thread::sleep(Duration::from_millis(100));
 
 		for i in (0..5).rev() {
+			self.port.discard_buffers()?;
+			std::thread::sleep(Duration::from_millis(10));
 			self.port.write(b"U")?;
 
 			let mut buf = [0u8; 1];