Binary command language appendix a, Circuit control request response – Rockwell Automation 1775-S5_SR5,D17756.5.5 User Manual PLC-3 FAMILY I/0 User Manual

Page 133

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Binary Command Language

Appendix A

A-5

Circuit Control Request Response

The scanner response to a master’s CCR is a fourteen byte response.

STX Rev

Series

Control

Code

Number

of

Bytes

Mod Type

and

thumbwheel

Max

command

block size

Max

response

block size

ETX

Current Character

Checksum

Current

command

block seq

response

block seq

timeout

value

Protocol

fault code

Command:

Description:

STX (start of text)

the first byte of the control block (02 hex).

Control Code

Value echoes the control code (byte two) of the

CCR.

Length of response block

Count of the remaining bytes including this byte and

the ETX.

Module type and thumbwheel number

Module type in the upper four bits and the

thumbwheel number in the lower four bits.

Scanner Series

Scanner module's series number.

Scanner Revision

Scanner module's revision number.

Maximum command block size

Scanner module's maximum command block size in

bytes.

Maximum response block size

Scanner module's maximum response block size in

bytes.

Current command block sequence

The current command block sequence count as

maintained by the scanner.

Current response block sequence

The current response block sequence count as

maintained by the scanner.

Character timeout value

The character timeout value in 10's of ms. If zero

then see Table A.A for default.

Protocol fault code

The protocol fault code. The possible fault codes

are listed in Table A.B.

ETX (End of text)

03 hex.

Checksum

The last byte in the CCR response is a checksum.

The checksum is the least significant eight bits of

the sum of all the above bytes in the response.

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