Return query data, Restart communications option, Listen only mode – Basler Electric BE1-11 Modbus Protocol User Manual

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9424200774 Rev B

Response

The response message contains the data queried. The data block contains the block length in bytes
followed by the data (one Data Hi byte and one Data Lo byte) for each requested register.

Reading an unassigned holding register returns a value of zero.

Device Address
Function Code =

03 (hex)

Byte Count
Data Hi (For each requested register, there is one Data Hi and one Data Lo.)
Data Lo
.
.
Data Hi
Data Lo
CRC Hi error check
CRC Lo error check

Return Query Data

This query contains data to be returned (looped back) in the response. The response and query
messages should be identical. If the query is a broadcast (device address = 0), no response message is
returned.


Device Address
Function Code =

08 (hex)

Subfunction Hi =

00 (hex)

Subfunction Lo =

00 (hex)

Data Hi =

xx (don't care)

Data Lo =

xx (don't care)

CRC Hi error check
CRC Lo error check

Restart Communications Option

This query causes the remote communications function of the BE1-11 to restart, terminating an active
listen only mode of operation. No effect is made upon primary BE1-11 operations. Only the remote
communications function is affected. If the query is a broadcast (device address = 0), no response
message is returned.

If the BE1-11 receives this query while in the listen only mode, no response message is generated.
Otherwise, a response message identical to the query message is transmitted prior to the
communications restart.

Device Address
Function Code =

08 (hex)

Subfunction Hi =

00 (hex)

Subfunction Lo =

01 (hex)

Data Hi =

xx (don't care)

Data Lo =

xx (don't care)

CRC Hi error check
CRC Lo error check

Listen Only Mode

This query forces the addressed BE1-11 to the listen only mode for Modbus communications, isolating it
from other devices on the network. No responses are returned.

General Information

BE1-11

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