Example command and response, Figure 4.17 – Rockwell Automation 900 Temperature Controller Communications Functions - Series B User Manual

Page 75

Publication 900-UM004D-EN-E - July 2010

Modbus Communications Procedure

4-17

Error Occurred

Example Command and Response

The following example shows the command/response for a Stop command.
(In this case, the slave address is H’01.)

Stop command (command code: H’01; related information: 01)

· Address: H’0000 (fixed)

Write data: H’0101 (Run/Stop, Stop command)

Figure 4.17

Table 4.14

Function
code

Error code

Name

Description

H’86

H’02

Variable address
error

• The write variable address is

incorrect.

• The variable area number (2-byte

data) is wrong, or the address is
not 0000 or FFFF.

H’03

Variable data
error

The write data is incorrect.
• The write data is out of the

setting range.

• Command code or related

information is incorrect

H’04

Operation error

The Controller cannot write the data
in its present operating status.
• The Communications Writing

parameter is set to “OFF”
(disabled). The command is
received regardless of the
Communications Writing
parameter setting (ON/OFF).

• Writing was attempted from

setup area 0 to setup area 1.

• Writing was attempted to a

protected parameter from
outside the protect level.

• AT execution was in progress.
• Processing could not be

01 06 00 00 01 01 49 9A(CRC-16)

Command:
Response: