diff --git a/Src/SerialPortHalfDuplexIO.c b/Src/SerialPortHalfDuplexIO.c
index 61a65ce..bf6248b 100644
--- a/Src/SerialPortHalfDuplexIO.c
+++ b/Src/SerialPortHalfDuplexIO.c
@@ -40,7 +40,12 @@ static uint16_t vSerialPortHalfDuplexTransmit(tSerialPortHalfDuplex *io, uint8_t
 
     uint16_t result = io->serialPortIo->transmit(io->serialPortIo->env, data, size, timeout);
 
+
+#ifndef HALF_DUPLEX_NO_DELAY
     SystemDelayMs(5);
+#else
+
+#endif
 
     GpioPinSet(io->transmitePin, false);
     GpioPinSet(io->recivePin, true);