YOKOGAWA UTAdvanced Series, User Manual

Page: 47 / 866

3-16
IM 05P07A01-01EN

66 Random reading

Function
The register data of register Nos. specified at random is read.
• Register Nos. can be specified from all register areas.
• The maximum number of registers that can be set is 100.
• For details on the response format at an error, see “ ● Response in an error state ” in
“3.1.3 Configuration of Responses (response from UTAdvanced).”

Message (during normal operation)
Element
Message start
mark (:)
Address No.
(ADRS)
Function code
(0x42)
Number of
specified
registers
Byte count
(Note 1)
Number of bytes in RTU mode None 1 1 2 1
Number of bytes in ASCII
mode
1 2 2 4 2
Continuation of message
Specified
Register No.
• • •
Specified
Register No
Error check
Message
end mark
(CR+LF)
2 • • • 2 2 None
4 • • • 4 2 2

Response (during normal operation)
Element
Message start
mark (:)
Address No.
(ADRS)
Function code
(0x42)
Byte count
(Note 1)
Register
conten
• • •
Number of bytes in RTU mode None 1 1 1 2 • • •
Number of bytes in ASCII
mode
1 2 2 2 4 • • •
Continuation of response
Register
content
Error check
Message end
mark (CR+LF)
2 2 None
4 2 2
Note 1: Byte count = 2 x number of read registers
3.1 Modbus Communication