Mitsubishi Electric FR-E700 Instruction Manual page 493

Parameter
Diagnostics (diagnosis of functions) (H08 or 08)
● A communication check can be made since the query message is sent and the query message is
returned as it is as the return message (subfunction code H00 function).
Subfunction code H00 (Return query data)
● Query message
³ Transaction
identifier
H
(8 Bits)
● Normal response (Response message)
³ Transaction
identifier
H
(8 Bits)
● Query message setting
Message
³
Transaction identifier
·
Protocol Identifier
»
Length field
¿
Unit identifier
´
Function
²
Subfunction
¶
Data
Tab. 6-127: Explanation of the query message
● Content of normal response
With a normal response, the contents in the response are the same as those in ³ to ¶ of the
query message.
FR-E700 SC EC/ENE
· Protocol
» Length field
identifier
L H L H
(8 Bits) (8 Bits) (8 Bits) (8 Bits)
· Protocol
» Length field
identifier
L H L H
(8 Bits) (8 Bits) (8 Bits) (8 Bits)
Description
The master adds the data for the purpose of transaction control.
The same data is returned in the response from the slave.
Fixed to 0. (When the slave receives data other than 0, it does not send the response
message.)
0 is returned in the response from the slave.
The data length from the unit identifier to the data is stored in byte.
Fixed to 255
Set H08.
Set H0000.
Any data 2 bytes long can be set. The setting range is H0000 to HFFFF.
¿ Unit
´ Function
identifier
L
(8 Bits)
(8 Bits) (8 Bits)
¿ Unit
´ Function
identifier
L
(8 Bits)
(8 Bits) (8 Bits)
MODBUS®/TCP (FR-E700 SC ENE)
² Subfunction
H08 H00 H00
(8 Bits) (8 Bits) (8 Bits)
² Subfunction
H08 H00 H00
(8 Bits) (8 Bits) (8 Bits)
¶ Data
H L
(8 Bits)
¶ Data
H L
(8 Bits)
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