From 9b6e8799b05acabc0845666c2dde8f8b43b72b22 Mon Sep 17 00:00:00 2001
From: Eveldee <eveldee0680@live.fr>
Date: Tue, 24 Nov 2020 15:28:51 +0100
Subject: [PATCH] Add timeout

---
 WaveshareUARTFingerprintSensor/FingerprintSensor.cs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/WaveshareUARTFingerprintSensor/FingerprintSensor.cs b/WaveshareUARTFingerprintSensor/FingerprintSensor.cs
index 9e3531b..12920f4 100644
--- a/WaveshareUARTFingerprintSensor/FingerprintSensor.cs
+++ b/WaveshareUARTFingerprintSensor/FingerprintSensor.cs
@@ -17,6 +17,7 @@ namespace WaveshareUARTFingerprintSensor
     {
         public const string PrimarySerialPort = "/dev/ttyAMA0";
         public const string SecondarySerialPort = "/dev/ttyS0";
+        public const int DefaultTimeout = 10_000;
 
         public string PortName { get; }
 
@@ -68,13 +69,16 @@ namespace WaveshareUARTFingerprintSensor
             return checksum;
         }
 
-        private (byte first, byte second, ResponseType responseType) SendAndReceive(CommandType commandType, byte first, byte second, byte third)
+        private (byte first, byte second, ResponseType responseType) SendAndReceive(CommandType commandType, byte first, byte second, byte third, int timeout = DefaultTimeout)
         {
             // Command packet
             byte[] buffer = { PacketSeparator, (byte)commandType, first, second, third, 0, 0, PacketSeparator };
 
             lock (_lock)
             {
+                // Set timeout
+                _serialPort.WriteTimeout = timeout;
+                _serialPort.ReadTimeout = timeout;
 
                 // Checksum
                 buffer[6] = ComputeChecksum(buffer);