X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/782614dbb55addcae8c9d4d9e1ce3dec81287282..e39f3378a21ae5076e8c49bc728c20e436e3a69f:/Projects/XPLAINBridge/Lib/SoftUART.c

diff --git a/Projects/XPLAINBridge/Lib/SoftUART.c b/Projects/XPLAINBridge/Lib/SoftUART.c
index ddd983a91..152c4e187 100644
--- a/Projects/XPLAINBridge/Lib/SoftUART.c
+++ b/Projects/XPLAINBridge/Lib/SoftUART.c
@@ -1,6 +1,6 @@
 /*
              LUFA Library
-     Copyright (C) Dean Camera, 2011.
+     Copyright (C) Dean Camera, 2012.
 
   dean [at] fourwalledcubicle [dot] com
            www.lufa-lib.org
@@ -9,7 +9,7 @@
 /*
   Copyright 2010  David Prentice (david.prentice [at] farming [dot] uk)
   Copyright 2010  Peter Danneger
-  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+  Copyright 2012  Dean Camera (dean [at] fourwalledcubicle [dot] com)
 
   Permission to use, copy, modify, distribute, and sell this
   software and its documentation for any purpose is hereby granted
@@ -52,7 +52,7 @@ static uint8_t RX_BitsRemaining;
 static uint8_t RX_Data;
 
 
-/** Initialises the software UART, ready for data transmission and reception into the global ring buffers. */
+/** Initializes the software UART, ready for data transmission and reception into the global ring buffers. */
 void SoftUART_Init(void)
 {
 	/* Set TX pin to output high, enable RX pull-up */
@@ -81,8 +81,10 @@ ISR(INT0_vect, ISR_BLOCK)
 	/* Reset the number of reception bits remaining counter */
 	RX_BitsRemaining = 8;
 
-	/* Reset the bit reception timer */
-	TCNT1 = 0;
+	/* Reset the bit reception timer to -(1/2) of the total bit time, so that the first data bit is
+	 * sampled mid way through the total bit time, making reception more robust.
+	 */
+	TCNT1 = -(OCR1A >> 1);
 
 	/* Check to see that the pin is still low (prevents glitches from starting a frame reception) */
 	if (!(SRXPIN & (1 << SRX)))