Error handling and exception responses, Modbus/tcp, Modbus/tcp -3 – Basler Electric BE1-700 Modbus Protocol User Manual

Page 13: Table 1-1. timing considerations, Table 1-2. supported exception response codes

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9376700991 Rev D

BE1-700 Modbus™ Protocol

1-3

Table 1-1. Timing Considerations

Baud Rate

3.5 Character Time

(ms)

Message Tx Time(s)

128 Bytes

256 Bytes

2400

16.04

0.59

1.17

4800

8.021

0.29

0.59

9600

4.0104

0.15

0.29

19200

2.0052

0.07

0.15

Any query received that contains a non-existent device address, a framing error or CRC error is ignored.

No response is transmitted. Queries addressed to a BE1-700 with an unsupported function or illegal

values in the data block result in an error response message with an exception response code. The

exception response codes supported by the BE1-700 are provided in

Error Handling and Exception Responses

Table 1-2.

Table 1-2. Supported Exception Response Codes

Code

Name

Description

01

Illegal Function

The query Function/Subfunction Code is unsupported; query

read of more than 125 registers; query preset of more than 100

registers.

02

Illegal Data Address

A register referenced in the data block does not support queried

read/write; query preset of a subset of a numerical register

group.

03

Illegal Data Value

A preset register data block contains an incorrect number of

bytes or one or more data values out of range.

Modbus/TCP

This is an optional Ethernet-enabled interface using the Transmission Control Protocol/Internet Protocol

(TCP/IP) as described below. Emphasis is placed on the initial setup of the relay. Should questions arise,

please contact your sales representative or Technical Services at Basler Electric, Highland, Illinois.

The

BE1-700 relay comes with DHCP (Dynamic Host Configuration Protocol) enabled. Refer to Appendix

A, Setting Up a DHCP Server Between BE1-700 and PC, for information on setting up a DHCP server

between the BE1-700 and your PC using third-party software. To set a static IP address (recommended),

follow the instructions below. To verify or set DHCP, see the following description.

Make sure that the relay is connected to the network. Start the Basler Modbus/TCP Device Discovery

application that can be found on the CD provided with the relay. Wait at least 90 seconds after powering

on the relay and then click the Refresh button. A screen similar to

Change from DHCP to Static IP Address on a Hubbed/Switched Network with a DHCP Server

Running

Figure 1-1 will appear and display all

the Modbus/TCP-enabled units connected to your network.

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