2014-
02
40
Commands
7.3.5
MODBUS exception codes
The device issues a response for each MODBUS transaction. The following table contains a list
of possible exception codes:
7.4
Communication via Ethernet/IP
7.4.1
General information on communication via Ethernet/IP
Ethernet/IP is an open fieldbus standard, which enables the exchange of data between
programmable logic controllers (PLCs), PCs, control systems, monitoring systems, sensors
Please visit the ODVA website at www.odva.org for more information about Ethernet/IP.
7.4.2
Performance spectrum
■
Implicit message
■
Explicit message
■
PCCC
7.4.3
PLC settings for implicit communication
The following parameters must be configured in addition to the IP address:
The lower limit of the RPI is 10 ms.
7.4.4
Data/Command transfer
Data is exchanged with the control interface using commands that the device recognizes.
There is an important difference between these commands and commands used for TCP/IP
and MODBUS protocols: Ethernet/IP commands do not contain parameters for the command
length.
The commands are transferred via Ethernet/IP objects, i.e., objects from classes 04h, 64h, and
65h. There are always two different modes available, which may not be confused: "Mixed
mode" and "Separated mode".
Code
Name
Description
01
Illegal function
The function code is not: 03h, 16h, 17h.
02
Illegal data address
The registers to be written or read are outside of the
defined range.
03
Illegal data value
The number of data sets to be read or written is invalid.
04
Slave device failure
Internal error
06
Slave device busy
An attempt is made to access a channel that is already
being used by another client.
0A
Gateway path
unavailable
The device ID is not 1 or 2.
Table 7.15
Exceptions of MODBUS transactions
Assembly instance
Size (32 bits)
Input
150 - 162 ( 50d)
2-15*
Output
100 - 112
2-15*
Configuration
112
0
Table 7.16
PLC settings for implicit communication
