• 01 = Read multiple bits (%Q)
• 02 = Read multiple discrete bits (%I)
• 03 = Read multiple words (%MW)
• 04 = Read multiple input words (%IW)
• 05 = Write single bit (%Q)
• 06 = Write single words (%MW)
• 07 = Read Exception Status (For serial line only)
• 08 = Diagnostic with the following sub-functions attached for serial line only:
  • Sub-function code 00 “echo mode" (Return Query Data)
  • Sub-function code 01 (Restart Communication Option)
  • Sub-function code 02 (Return Diagnostic Register)
  • Sub-function code 03 (Change ASCII Input Delimiter)
  • Sub-function code 04 (Force Listen Only Mode)
  • Sub-function code 10 (Clear Counters and Diagnostic Register)
  • Sub-function code 11 "counter 1" (Return Bus Message Count)
  • Sub-function code 12 "counter 2" (Return Bus Communication Error Count)
  • Sub-function code 13 "counter 3" (Return Bus Exception Error Count)
  • Sub-function code 16 "counter 6" (Return Slave NAK Count)
  • Sub-function code 17 "counter 7" (Return Slave Busy Count)
  • Sub-function code 18 "counter 8" (Return Bus Character Overrun Count)
• 11 = Get Com Event Counter (For serial line only)
• 12 = Get Com Event Log (For serial line only
• 15 = Write multiple bits (%Q)
• 16 = Write multiple words (%MW)
• 22 = Mask write register (As a Server only)
• 23 = Read/Write multiple registers (%MW)

Released for:Schneider Electric UK