diff --git a/IO_Modbus.cpp b/IO_Modbus.cpp
index 01bbc4a..876590a 100644
--- a/IO_Modbus.cpp
+++ b/IO_Modbus.cpp
@@ -253,7 +253,7 @@ void ModbusRTUComm::writeAdu(ModbusADU& adu) {
   if (_rePin >= 0) digitalWrite(_rePin, HIGH);
   _serial.write(adu.rtu, adu.getRtuLen());
   _serial.flush();
-  delayMicroseconds(_postDelay);
+  ///delayMicroseconds(_postDelay);
   if (_dePin >= 0) digitalWrite(_dePin, LOW);
   if (_rePin >= 0) digitalWrite(_rePin, LOW);
 }
@@ -498,7 +498,9 @@ Modbus::Modbus(uint8_t busNo, HardwareSerial serial, unsigned long baud, uint16_
     //ArduinoPins::fastWriteDigital(_transmitEnablePin, 0); // transmitter initially off
   //}
   
-  
+  //_serial->begin(baud);
+  //_modbusmaster.begin(baud);
+  //DIAG(F("ModbusInit: %d %d"), _transmitEnablePin, _baud);
   // Add device to HAL device chain
   IODevice::addDevice(this);
 
@@ -507,8 +509,16 @@ Modbus::Modbus(uint8_t busNo, HardwareSerial serial, unsigned long baud, uint16_
   _busList = this;
 }
 
+void Modbus::_begin() {
+  ModbusRTUMaster _modbusmaster(*_serial, _transmitEnablePin, -1);
+  _serial->begin(_baud);
+  _modbusmaster.begin(_baud);
+#if defined(DIAG_IO)
+  _display();
+#endif
+}
 
-// Main loop function for CMRIbus.
+// Main loop function for Modbus.
 // Work through list of nodes.  For each node, in separate loop entries
 // send initialisation message (once only);  then send
 // output message;  then send prompt for input data, and 
@@ -517,27 +527,30 @@ Modbus::Modbus(uint8_t busNo, HardwareSerial serial, unsigned long baud, uint16_
 void Modbus::_loop(unsigned long currentMicros) {
   
   _currentMicros = currentMicros;
-  if (_currentNode == NULL) {
-    // If we're between read/write cycles then don't do anything else.
-    if (_currentMicros - _cycleStartTime < _cycleTime) return;
-    _currentNode = _nodeListStart;
-  }
-  _cycleStartTime = _currentMicros;
+  
+  //if (_currentNode == NULL) {
+    //_currentNode = _nodeListStart;
+    
+  //}
+  if (_currentMicros - _cycleStartTime < _cycleTime) return;
   if (_currentNode == NULL) return;
+  
   const char* errorStrings[16] = { "success", "invalid id", "invalid buffer", "invalid quantity", "response timeout", "frame error", "crc error", "unknown comm error", "unexpected id", "exception response", "unexpected function code", "unexpected response length", "unexpected byte count", "unexpected address", "unexpected value", "unexpected quantity" };
   
   uint8_t error;
-  error = modbusmaster->writeMultipleHoldingRegisters(_currentNode->getNodeID(), 0, _currentNode->holdingRegisters, _currentNode->getNumHoldingRegisters());
-  if (error != 0) DIAG(F("ModbusHR: %d %d %d %s"), _currentNode->getNodeID(), 0, _currentNode->getNumHoldingRegisters(), errorStrings[error]);
+  //error = _modbusmaster->writeMultipleHoldingRegisters(_currentNode->getNodeID(), 0, _currentNode->holdingRegisters, _currentNode->getNumHoldingRegisters());
+  //if (error != 0) DIAG(F("ModbusHR: %d %d %d %s"), _currentNode->getNodeID(), 0, _currentNode->getNumHoldingRegisters(), errorStrings[error]);
 
-  error = modbusmaster->writeMultipleCoils(_currentNode->getNodeID(), 0, _currentNode->coils, _currentNode->getNumCoils());
+  error = _modbusmaster->writeMultipleCoils(_currentNode->getNodeID(), 0, _currentNode->coils, _currentNode->getNumCoils());
   if (error != 0) DIAG(F("ModbusMC: %d %d %d %s"), _currentNode->getNodeID(), 0, _currentNode->getNumCoils(), errorStrings[error]);
 
-  error = modbusmaster->readDiscreteInputs(_currentNode->getNodeID(), 0, _currentNode->discreteInputs, _currentNode->getNumDiscreteInputs());
+  error = _modbusmaster->readDiscreteInputs(_currentNode->getNodeID(), 0, _currentNode->discreteInputs, _currentNode->getNumDiscreteInputs());
   if (error != 0) DIAG(F("ModbusDI: %d %d %d %s"), _currentNode->getNodeID(), 0, _currentNode->getNumDiscreteInputs(), errorStrings[error]);
 
-  error = modbusmaster->readInputRegisters(_currentNode->getNodeID(), 0, _currentNode->inputRegisters, _currentNode->getNumInputRegisters());
-  if (error != 0) DIAG(F("ModbusIR: %d %d %d %s"), _currentNode->getNodeID(), 0, _currentNode->getNumInputRegisters(), errorStrings[error]);
+  //error = _modbusmaster->readInputRegisters(_currentNode->getNodeID(), 0, _currentNode->inputRegisters, _currentNode->getNumInputRegisters());
+  //if (error != 0) DIAG(F("ModbusIR: %d %d %d %s"), _currentNode->getNodeID(), 0, _currentNode->getNumInputRegisters(), errorStrings[error]);
+  //delayUntil(_currentMicros + _cycleTime * 1000UL);
+  _cycleStartTime = _currentMicros;
 }
 
 // Link to chain of Modbus instances
diff --git a/IO_Modbus.h b/IO_Modbus.h
index ee06d55..8d6b940 100644
--- a/IO_Modbus.h
+++ b/IO_Modbus.h
@@ -339,21 +339,14 @@ private:
   static Modbus *_busList; // linked list of defined bus instances
 
 public:
-  static void create(uint8_t busNo, HardwareSerial& serial, unsigned long baud, uint16_t cycleTimeMS=500, int16_t transmitEnablePin=VPIN_NONE) {
+  static void create(uint8_t busNo, HardwareSerial& serial, unsigned long baud, uint16_t cycleTimeMS=500, int16_t transmitEnablePin=51) {
     new Modbus(busNo, serial, baud, cycleTimeMS, transmitEnablePin);
   }
   HardwareSerial *_serial;
-  ModbusRTUMaster *modbusmaster;
+  ModbusRTUMaster *_modbusmaster;
 
   // Device-specific initialisation
-  void _begin() override {
-    ModbusRTUMaster modbusmaster(*_serial, _transmitEnablePin);
-    _serial->begin(_baud, SERIAL_8N1);
-    modbusmaster.begin(_baud);
-  #if defined(DIAG_IO)
-    _display();
-  #endif
-  }
+  void _begin() override;
 
   // Loop function (overriding IODevice::_loop(unsigned long))
   void _loop(unsigned long currentMicros) override;