Rockwell Automation 1775-S5_SR5,D17756.5.5 User Manual PLC-3 FAMILY I/0 User Manual

Page 151

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Binary Command Language

Appendix A

A-23

The processor responds to a write block command with one of the
following response codes:

Response Codes

Hex

Description

00

Success

04

Address unknown

05

Size too big

06

Access not allowed

08

Address not complete

0F

No privilege

If the size too big response returns, the processor stores data which fits
into the existing memory locations. The rest is lost. If any code besides
success or size too big is returned, no data is written into memory. The
following response block shows a successful write block command:

STX

02

OSC

01

SIZ

01

RSP

00

ETX

03

CHK

07

The size is specified in one byte. This is true of all size specifiers within
the data buffer of a response block.

ReadĆModifyĆWrite Command

Hex: 16

Parameters: Address of the word to modify, one word AND mask, one
word OR mask

Description: The following example command block executes the
read-modify-write command:

STX

02

ISC

0D

SIZ

08

CMD

16

24

05

03

ETX

03

CHK

07

DAT

55

55

0F

0F

The data bytes store:

address mask (24 hex)
first and second address bytes (05, 03 hex)
lower and upper bytes of AND mask (55 hex)
lower and upper bytes of OR mask (0F hex)

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