Random Read And Write - Mitsubishi Electric MELSEC IQ-R series Reference Manual

8.3

Random Read and Write

Read or write device values by specifying the device numbers. It can be specified with discontinuous device numbers.
Random read in word units (command: 0403)
Read values from devices in word units and double word units. It can be specified with discontinuous device number.
When accessing any of the following devices, use the device extension specification (subcommand: 008).
• Link direct device
• Module access device
• CPU buffer memory access device
For the message format for device extension specification, refer to the following section.
Page 438 Read/Write by Device Extension Specification
Message format
The following shows the message format of the request data and response data of the command.
■Request data
Command Subcommand
Device
(first point)
Device for word access
■Response data
Data read (first point) Data read (mth point)
Read data in word units
The value of read device is stored in word units and in double word units. The data order differs between ASCII code or binary
code. (Page 74 Read data, write data)
Data specified by request data
■Command
Frame
4C/3C/4E/3E frame
2C frame
Monitor condition
Number of word access
specification
points (m points)
designation
Device Device
(first point)
(mth point)
Device for double word access
Data read (first point)
Data read in double word units
ASCII code
0 4 0 3
30 34 30 33
H H H H
5
35
H
Number of double word
access points (n points)
Device
(nth point)
Data read (nth point)
Binary code
03 04
H H

8.3 Random Read and Write
8 DEVICE ACCESS
99
8