On-Demand Function Control Procedure During User Frame Use; Data Communication Using The Ascii Code - Mitsubishi Electric MELSEC iQ-R Series User Manual

14.3
On-Demand Function Control Procedure During
User Frame Use
This section explains the control procedure when on-demand data is transmitted to a target device with the on-demand
function by using a user frame.

Data communication using the ASCII code

Control procedure when two-word send data (1234H, 5678H) is designated by ONDEMAND instruction
• Set the "Communication protocol setting" to any one of the "MC protocol (format 1 to format 4) ".
• Set the "Station number" to "0".
• Set the "Word/byte units designation" to word unit.
• Set the "On-demand user frame specification" items to the following:
Start frame No. 1st: 02H
Start frame No. 2nd: 3EBH
Final frame No. 1st: 401H
Final frame No. 2nd: 0H (No specification)
• User frame registration
User frame No.
02H(2)
3EBH(1003)
401H(1025)
14 ON-DEMAND DATA COMMUNICATIONS USING USER FRAMES
270

14.3 On-Demand Function Control Procedure During User Frame Use

User frame (Registered code)
02H
F9H, 00H, 00H, FFH, FFH, 00H
03H, FFH, F1H
Contents of user frame registration
Data code from STX to host station number matched to 3C frame, format 1
Data code of ETX, sum check code equivalent to 3C frame, format 1