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Rockwell Automation 1775-KA PLC-3 Communication Adapter Module User Manual User Manual

Page 178

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Message Formats

Appendix A

AĆ16

B. Format when reporting an error

DLE

SRC

STX

DST

C

4F

S

TNS

MD

TS

TNS

DLE ETX

BCC

ETX

STS

Where the extended status byte is optional.

Word Range Write

Use this write command with a word symbol, a file symbol plus a word
offset, or a logical address as a starting address. This starting address
must point to a word in a file. This write command can write a block of
data. The function code is 0 (zero). A special case of this command is the
single word write, where the data field is only one word long.

Command Format:

A. Word symbol address

DLE

SRC

C

0

S

TNS

MD

F

TS

TNS

STX

FNC PACKET

00

ASCII symbol

(8 characters max)

DLE ETX

BCC

00

W/F

00

OFFSET

TOTAL

TRANS

00

DST

ASCII s

(8 characters max)

DATA - Max of 228 bytes

or 114 words

B. File symbol address plus word offset

DLE

SRC

C

0

S

TNS

MD

F

TS

TNS

STX

FNC PACKET

00

ASCII symbol

(8 characters max)

DLE ETX

BCC

00

OFFSET

TOTAL

TRANS

00

DST

ASCII

(8 characters max)

DATA - Max of 226 bytes

or 113 words

W/F

01

WORD

OFFSET

C. Logical address

DLE

SRC

C

0

S

TNS

MD

F

TS

TNS

STX

FNC PACKET

00

DLE ETX BCC

OFFSET

TOTAL

TRANS

DST

DATA - Max length is 239 bytes minus

PLC-3 logical address

(2-51 bytes)

the length of the PLC-3 logical address

(must be an even number of bytes)