ModbusRTU Stability fixes

- Fixed early bus release if no transactional callback assigned for read/write Hreg/Coil
- Fixed possible responce loss for ESP32 master

Author: emelianov

README.md

@@ -63,6 +63,9 @@ V1.02](http://www.modbus.org/docs/Modbus_over_serial_line_V1_02.pdf)
 ## Last Changes
 
 ```diff
+// 3.0.5
++ ModbusRTU: Fix early bus release if no callback
++ ModbusRTU ESP32: Fix potential responce loss
 // 3.0.4
 + ModbusIP: Fixed missed server connection free in destructor
 + Fixed addition of missing registers in .poll*() calls

library.properties

@@ -1,5 +1,5 @@
 name=modbus-esp8266
-version=3.0.4
+version=3.0.5
 author=Andre Sarmento Barbosa, Alexander Emelianov
 maintainer=Alexander Emelianov<[email protected]>
 sentence=Modbus RTU and Modbus TCP Library for ESP8266/ESP32

src/ModbusRTU.cpp

@@ -111,13 +111,12 @@ bool ModbusRTU::rawSend(uint8_t slaveId, uint8_t* frame, uint8_t len) {
     _port->write(frame, len); 	// Send PDU
     _port->write(newCrc >> 8);	//Send CRC
     _port->write(newCrc & 0xFF);//Send CRC
-	#ifdef ESP32
-    portEXIT_CRITICAL(&mux);
- 	#endif
     _port->flush();
     if (_txPin >= 0)
         digitalWrite(_txPin, _direct?LOW:HIGH);
-	//delay(_t);
+	#ifdef ESP32
+    portEXIT_CRITICAL(&mux);
+ 	#endif
 	return true;
 }
 
@@ -264,12 +263,12 @@ bool ModbusRTU::cleanup() {
 
 uint16_t ModbusRTU::writeHreg(uint8_t slaveId, uint16_t offset, uint16_t value, cbTransaction cb) {
     readSlave(offset, value, FC_WRITE_REG);
-	return send(slaveId, HREG(offset), cb, nullptr, cb);
+	return send(slaveId, HREG(offset), cb, nullptr);
 }
 
 uint16_t ModbusRTU::writeCoil(uint8_t slaveId, uint16_t offset, bool value, cbTransaction cb) {
 	readSlave(offset, COIL_VAL(value), FC_WRITE_COIL);
-	return send(slaveId, COIL(offset), cb, nullptr, cb);
+	return send(slaveId, COIL(offset), cb, nullptr);
 }
 
 uint16_t ModbusRTU::readCoil(uint8_t slaveId, uint16_t offset, bool* value, uint16_t numregs, cbTransaction cb) {
@@ -282,14 +281,14 @@ uint16_t ModbusRTU::readCoil(uint8_t slaveId, uint16_t offset, bool* value, uint
 uint16_t ModbusRTU::writeCoil(uint8_t slaveId, uint16_t offset, bool* value, uint16_t numregs, cbTransaction cb) {
 	if (numregs < 0x0001 || numregs > 0x07D0) return false;
 	writeSlaveBits(COIL(offset), offset, numregs, FC_WRITE_COILS, value);
-	return send(slaveId, COIL(offset), cb, nullptr, cb);
+	return send(slaveId, COIL(offset), cb, nullptr);
 }
 
 
 uint16_t ModbusRTU::writeHreg(uint8_t slaveId, uint16_t offset, uint16_t* value, uint16_t numregs, cbTransaction cb) {
 	if (numregs < 0x0001 || numregs > 0x007D) return false;
 	writeSlaveWords(HREG(offset), offset, numregs, FC_WRITE_REGS, value);
-	return send(slaveId, HREG(offset), cb, nullptr, cb);
+	return send(slaveId, HREG(offset), cb, nullptr);
 }