X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/1d433d4506113c95285f633e3553ff62d4cfd05d..46aea9d4ce0948f2340bfddc1c5a1bcc889e8840:/Projects/XPLAINBridge/Lib/SoftUART.c diff --git a/Projects/XPLAINBridge/Lib/SoftUART.c b/Projects/XPLAINBridge/Lib/SoftUART.c index 1da223676..9ee103d92 100644 --- a/Projects/XPLAINBridge/Lib/SoftUART.c +++ b/Projects/XPLAINBridge/Lib/SoftUART.c @@ -51,7 +51,8 @@ static uint8_t RX_BitsRemaining; /** Temporary data variable to hold the byte being received as it is shifted in */ 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 */ @@ -80,8 +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)))