Modbus MFU Option Card Installation Manual
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Publication PUB091-003-00_0119
Loopback Test – Function code 08
Supported Diagnostic Codes
Diagnostic
Code
Function
00
Return query data
01
Restart communications
02
Return diagnostic register
04
Force slave listen only
10
Clear diagnostic counts
11
Return bus message count
17
Return slave busy count
Diagnostic Register contents
Location
(Bit)
Description
0
EEPROM timeout error
1
Checksum error
2
Checksum error
3
Checksum error
4
Watchdog recovery
5
Reserved
6
Reserved
7
Reserved
8
Reserved
9
Reserved
10
Reserved
11
Reserved
12
RS-485 highway ESD active
13
Auxiliary control input active
14
Positioner MIT active
15
Positioner enable flag
Bits 0 to 7 generate the “error” bit in the digital status register.
Bit 0
indicates an EEPROM timeout has occurred.
Bit 1 to 3
indicates that a checksum error has occurred
Bit 4
indicates whether the module has been reset by the watchdog.
Bit 12
indicates that an ESD has been received via the RS-485 highway.
Bit 13
shows that an auxiliary input, (enabled for control), is active.
Bit 14
when set the MIT is active.
Bit 15
when set the actuator is operating in positioning mode
Report Slave ID – Function code 17
Byte
Data
0 – 25
‘00Rotork IQ Modbus Module.’
26 – 47
‘Software version: Mxxx’ (where xxx is the revision number)