From 1a130eed6c990701642afc1a1e9738dfd86b0d4b Mon Sep 17 00:00:00 2001 From: Dean Camera Date: Tue, 15 Mar 2011 04:02:15 +0000 Subject: Updated the software USART code in the XPLAIN Bridge application so that the incomming bits are sampled at their mid-point instead of starting point, to give maximum reliability (thanks to Anton). --- Projects/XPLAINBridge/Lib/SoftUART.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'Projects/XPLAINBridge') diff --git a/Projects/XPLAINBridge/Lib/SoftUART.c b/Projects/XPLAINBridge/Lib/SoftUART.c index ddd983a91..370e806ac 100644 --- a/Projects/XPLAINBridge/Lib/SoftUART.c +++ b/Projects/XPLAINBridge/Lib/SoftUART.c @@ -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))) -- cgit v1.2.3