https://www.qec.tw/zh/86duino-library/modbus/modbusmasternode/modbusmasternode-writesinglecoil/
ModbusMasterNode.writeSingleCoil() - QEC
May 27, 2022 - Description Send a packet command to the Slave node to write to a single Coil register. Syntax node1.writeSingleCoil(write_address, value) Parameters
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