diff options
Diffstat (limited to 'Projects/XPLAINBridge/Lib')
| -rw-r--r-- | Projects/XPLAINBridge/Lib/SoftUART.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/Projects/XPLAINBridge/Lib/SoftUART.c b/Projects/XPLAINBridge/Lib/SoftUART.c index 458a505cd..90c23b71d 100644 --- a/Projects/XPLAINBridge/Lib/SoftUART.c +++ b/Projects/XPLAINBridge/Lib/SoftUART.c @@ -76,15 +76,21 @@ void SoftUART_Init(void) /** ISR to detect the start of a bit being sent to the software UART. */ ISR(INT0_vect, ISR_BLOCK) { - /* Reset and start the reception timer */ - TCNT1 = 0; - TCCR1B = ((1 << CS10) | (1 << WGM12)); - /* Reset the number of reception bits remaining counter */ RX_BitsRemaining = 8; + + /* Reset the bit reception timer */ + TCNT1 = 0; + + /* Check to see that the pin is still low (prevents glitches from starting a frame reception) */ + if (!(SRXPIN & (1 << SRX))) + { + /* Disable start bit detection ISR while the next byte is received */ + EIMSK = 0; - /* Disable start bit detection ISR while the next byte is received */ - EIMSK = 0; + /* Start the reception timer */ + TCCR1B = ((1 << CS10) | (1 << WGM12)); + } } /** ISR to manage the reception of bits to the software UART. */ @@ -133,7 +139,7 @@ ISR(TIMER3_COMPA_vect, ISR_NOBLOCK) TX_Data >>= 1; TX_BitsRemaining--; } - else if (USBtoUART_Buffer.Count) + else if (USBtoUART_Buffer.Count && !(RX_BitsRemaining)) { /* Start bit - TX line low */ STXPORT &= ~(1 << STX); |