Chapter 8 Serial Communication Module AH10SCM Type 5: Sending a control record, and receiving a full record: Sending a control record: The function field is 16#89. 『 Start bit 』 + 『 Length 』 + 『 Length (repeat) 』 + 『 Start bit (repeat) 』 + 『 Instrument address (IA) 』 + 『 Function field (FF) 』 + 『 Parameter index (PI) 』 + 『 Checksum (CS) 』 + 『 End mark 』 16#68+16#03+16#03+16#68+D0+16#89+D1+(Summation of the characters starting from IA to PI)+16#16 Start bit ─ Length ─ Length (repeat) ─ Start bit (repeat) The instrument address (IA) is read from D0. Function field (FF): 16#89 The parameter index (PI) is read from D1. 8-59