YOKOGAWA F3SP71-4S, User Manual

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3-9
IM 34M06P15-03E 2nd Edition: Jan. 31, 2012-00
3.9 Read File Record ($14)
Reads the values of multiple file records.
The amount of devices that can be accessed with a single request is 1 to 124 points.
Request Format (Master => Slave)
F030109.VSD
Function
Code
Data
$14
1-byte 1-byte
Length
（
7×m
）
Data
Reference
No.
$06
1-byte 2-byte
File Nos.
($0000 to $FFFF)
Read Starting Record
Nos.
($0000 to $270F)
2-byte
Sub-request 1
2-byte
Read Record Count
($0000 to $007C)
n1
Data
Reference
No.
$06
1-byte 2-byte
File Nos.
($0000 to $FFFF)
Read Starting Record
Nos.
($0000 to $270F)
2-byte
Sub-request m
2-byte
Read Record Count
($0000 to $007C)
nm
(a) Specify the sub-request count m so that the request PDU (protocol
data units) size does not exceed 253 bytes (m ≤ 35).
(b) Specify the total read points N (n1 + ... + nm) of each sub-request so
that the response PDU (protocol data units) size does not exceed 253
bytes.