Expose libmodbus's flush command

[pomplesiegel]

• Expose libmodbus's flush command to ModbusRTUServer API
• This command proved to be necessary for stable operation for large reads at low baud rates on the RP2040. May be important for cross-platform compatibility

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[github-actions]

Memory usage change @ 5c93b08

Board	flash	%	RAM for global variables	%
arduino:mbed_nano:nano33ble	🔺 0 - +8	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_opta:opta	🔺 0 - +72	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_portenta:envie_m7	N/A	N/A	N/A	N/A
arduino:megaavr:uno2018:mode=off	🔺 +12 - +12	+0.02 - +0.02	0 - 0	0.0 - 0.0
arduino:samd:mkrwifi1010	🔺 +8 - +16	0.0 - +0.01	0 - 0	0.0 - 0.0

Click for full report table

Board	examples/RTU/ModbusRTUClientKitchenSink flash	%	examples/RTU/ModbusRTUClientKitchenSink RAM for global variables	%	examples/RTU/ModbusRTUClientParameters flash	%	examples/RTU/ModbusRTUClientParameters RAM for global variables	%	examples/RTU/ModbusRTUClientToggle flash	%	examples/RTU/ModbusRTUClientToggle RAM for global variables	%	examples/RTU/ModbusRTUServerKitchenSink flash	%	examples/RTU/ModbusRTUServerKitchenSink RAM for global variables	%	examples/RTU/ModbusRTUServerLED flash	%	examples/RTU/ModbusRTUServerLED RAM for global variables	%	examples/RTU/ModbusRTUTemperatureSensor flash	%	examples/RTU/ModbusRTUTemperatureSensor RAM for global variables	%	examples/TCP/EthernetModbusClientToggle flash	%	examples/TCP/EthernetModbusClientToggle RAM for global variables	%	examples/TCP/EthernetModbusServerLED flash	%	examples/TCP/EthernetModbusServerLED RAM for global variables	%	examples/TCP/WiFiModbusClientToggle flash	%	examples/TCP/WiFiModbusClientToggle RAM for global variables	%	examples/TCP/WiFiModbusServerLED flash	%	examples/TCP/WiFiModbusServerLED RAM for global variables	%
arduino:mbed_nano:nano33ble	0	0.0	0	0.0	8	0.0	0	0.0	0	0.0	0	0.0	8	0.0	0	0.0	8	0.0	0	0.0	8	0.0	0	0.0
arduino:mbed_opta:opta	0	0.0	0	0.0	72	0.0	0	0.0	0	0.0	0	0.0	8	0.0	0	0.0	8	0.0	0	0.0	8	0.0	0	0.0	0	0.0	0	0.0	8	0.0	0	0.0
arduino:mbed_portenta:envie_m7	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
arduino:megaavr:uno2018:mode=off	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0	12	0.02	0	0.0
arduino:samd:mkrwifi1010	8	0.0	0	0.0	8	0.0	0	0.0	16	0.01	0	0.0	8	0.0	0	0.0	8	0.0	0	0.0	16	0.01	0	0.0	8	0.0	0	0.0	16	0.01	0	0.0	16	0.01	0	0.0	16	0.01	0	0.0

Click for full report CSV

Board,examples/RTU/ModbusRTUClientKitchenSink<br>flash,%,examples/RTU/ModbusRTUClientKitchenSink<br>RAM for global variables,%,examples/RTU/ModbusRTUClientParameters<br>flash,%,examples/RTU/ModbusRTUClientParameters<br>RAM for global variables,%,examples/RTU/ModbusRTUClientToggle<br>flash,%,examples/RTU/ModbusRTUClientToggle<br>RAM for global variables,%,examples/RTU/ModbusRTUServerKitchenSink<br>flash,%,examples/RTU/ModbusRTUServerKitchenSink<br>RAM for global variables,%,examples/RTU/ModbusRTUServerLED<br>flash,%,examples/RTU/ModbusRTUServerLED<br>RAM for global variables,%,examples/RTU/ModbusRTUTemperatureSensor<br>flash,%,examples/RTU/ModbusRTUTemperatureSensor<br>RAM for global variables,%,examples/TCP/EthernetModbusClientToggle<br>flash,%,examples/TCP/EthernetModbusClientToggle<br>RAM for global variables,%,examples/TCP/EthernetModbusServerLED<br>flash,%,examples/TCP/EthernetModbusServerLED<br>RAM for global variables,%,examples/TCP/WiFiModbusClientToggle<br>flash,%,examples/TCP/WiFiModbusClientToggle<br>RAM for global variables,%,examples/TCP/WiFiModbusServerLED<br>flash,%,examples/TCP/WiFiModbusServerLED<br>RAM for global variables,%
arduino:mbed_nano:nano33ble,0,0.0,0,0.0,8,0.0,0,0.0,0,0.0,0,0.0,8,0.0,0,0.0,8,0.0,0,0.0,8,0.0,0,0.0
arduino:mbed_opta:opta,0,0.0,0,0.0,72,0.0,0,0.0,0,0.0,0,0.0,8,0.0,0,0.0,8,0.0,0,0.0,8,0.0,0,0.0,0,0.0,0,0.0,8,0.0,0,0.0
arduino:mbed_portenta:envie_m7,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,,,,,,,,
arduino:megaavr:uno2018:mode=off,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0,12,0.02,0,0.0
arduino:samd:mkrwifi1010,8,0.0,0,0.0,8,0.0,0,0.0,16,0.01,0,0.0,8,0.0,0,0.0,8,0.0,0,0.0,16,0.01,0,0.0,8,0.0,0,0.0,16,0.01,0,0.0,16,0.01,0,0.0,16,0.01,0,0.0