YOKOGAWA UT150L, User Manual

Page: 47 / 60

IM 05C01E22-10E
4-9
Chapter 4 MODBUS Communication
4.2.4 Response Error Codes
●
Message Format in the Event of Error
If there is any inconsistency other then communication errors in a message, UT150L does nothing, but
returns the following message.
Element
Number of bytes in
RTU mode
*
The function code contains a function code (hexadecimal number) + 80 (hexadecimal number).
Number of bytes in
ASCII mode
Address Number
(ADR)
1
2
Function Code *
1
2
Error Code
1
2
Error Check
2
2
●
Error Codes in Response
Table 4-4 List of Error Codes
Error Code
01
02
Meaning
Function code error
D-register address error
Description
No function code exists.
Address out of the range has been specified.
03 D-register count error Number of D registers has been specified, being out of the range.
●
Even when a message is sent, no response returns if:
• Retransmission error (overrun, framing, parity, LRC, or CRC-16 error) was detected.
• Address in an instructed message is incorrect.
• Interval between data composing a message was 1 second or more.
• Broadcast is specified (address number: 00).
* As a measure against those, provide a timeout process in the communication functions of a higher-
level device or in communication programs.