ABB TPU2000R User Manual

TPU2000/2000R Modbus/Modbus Plus/ Modbus TCP/IP Automation Guide
248
Modbus Host
Modbus Slave Addr =1
Read from
4X Mapping
Slave
Addr.
Funct.
Code
03
Start
Addr
HI
Start
Addr
LO
Regs
Read
HI
Regs
Read
LO
Error
Check
EOT
SOT
Byte 1 …2……..3…….4…….5……6……..7….
Slave
Addr.
Funct.
Code
83
Exception
Code
Error
Check
EOTSOT
E
C
Network
Partner
V1.0
Error Generated- msb of Function Code Set to 1
Figure 5-73. Exception Code Example for Holding Register Read
Modbus Troubleshooting Tips
The Modbus Protocol contains a set of commands intended to assist with network troubleshooting. Those
commands are:
08 – Diagnostic Functions
0B –Fetch Communication Event Counter
0C- Fetch Communication Log
The TPU2000 and TPU2000R do support one sub function code of the Diagnostic Function 08. Modbus
Commands 0B and 0C are not supported.
Figure 5-74 lists the 08 Diagnostic Function Format.
Function 08 - Diagnostic Function
Modbus Host
E
C
Modbus Slave Addr =1
Slave
Addr.
Funct.
Code
08
Sub
Funct.
HI
Sub.
Funct.
LO
Data
HI
Data
LO
Error
Check
*
EOT
Byte 1 …2……..3…….4…….5……6……
SOT
Slave
Addr.
Funct.
Code
08
Sub
Funct.
HI
Sub.
Funct.
LO
Data
HI
Data
LO
Error
Check
*
EOT
Figure 5-74. Diagnostic Function Code
Only Sub function 00 is supported. Sub function 00 is the loop-back function. If the sub function hi and lo bytes
are 00 hex, whatever is placed in the data field by the host will be received by the TPU2000 or TPU2000R and
returned or looped back to the host.

ABB TPU2000R Specifications

General

Brand	ABB
Model	TPU2000R
Category	Computer Hardware
Language	English