Hi Sony,
Here is example with both WriteSingleCoil and WriteMultipleCoil. The Number (which is the bit number) in the channels, for MultipleCoil goes from 0 - 7 in Ch1 - 8 (first byte), and from 0 - 1 in Ch9 - 10 (second byte).
Master and Slave is the same as before. Note that process usually is Plc or IoComm, not 64 as in this example.
/Claes