X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=blobdiff_plain;f=firmware%2Fmodbus.c;fp=firmware%2Fmodbus.c;h=00a9370a05bdaa872ce14b38f95de35d194d275b;hb=6146a1caafd449cae4ce08134d763137424300c6;hp=4e8456354e1a5385d630eb7f4cd59cff0f6606a3;hpb=0c9ed6a110149013fd3690338fac0b33f760e0ed;p=openparking.git

diff --git a/firmware/modbus.c b/firmware/modbus.c
index 4e84563..00a9370 100644
--- a/firmware/modbus.c
+++ b/firmware/modbus.c
@@ -159,7 +159,7 @@ static mb_exception write_single_reg(uint16_t reg, uint16_t val)
 	return MB_OK;
 }
 
-void modbus_poll()
+uint8_t modbus_poll()
 {
 	bufptr_t packet_len;
 	uint16_t crc;
@@ -167,22 +167,22 @@ void modbus_poll()
 
 	ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
 		if (transmitting)
-			return;
+			return 0;
 
 		if (buf_len == 0) // nothing received yet
-			return;
+			return 0;
 
 		if (get_clock() - last_rx < REQ_TIMEOUT) // still receiving
-			return;
+			return 0;
 
 		if (buf_len < 4) { // too short
 			buf_len = 0;
-			return;
+			return 0;
 		}
 
 		if (buffer[0] != mb_unit_id) { // not for myself
 			buf_len = 0;
-			return;
+			return 0;
 		}
 
 		transmitting = 1; // disable further reads
@@ -197,7 +197,7 @@ void modbus_poll()
 			transmitting = 0;
 			buf_len = 0;
 		}
-		return;
+		return 1;
 	}
 
 	packet_len -= 2; // strip the CRC
@@ -234,6 +234,8 @@ void modbus_poll()
 	tx_ptr = 0;
 	ctl_pin_on();
 	UCSR0B |= _BV(UDRIE0);
+
+	return 1;
 }
 
 ISR(USART_RX_vect)