Rockwell Automation 1794-L34 FlexLogix Controller System User Manual User Manual

Page 37

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Publication 1794-UM001G-EN-P - January 2007

Communicate over Networks 37

The controller supports several instructions to manipulate ASCII
characters. The instructions are available in ladder diagram (LD) and
structured text (ST).

Read and write ASCII characters

Create and modify strings of ASCII characters

If you want to:

Use this instruction:

determine when the buffer contains termination characters

ABL

count the characters in the buffer

ACB

clear the buffer

ACL

clear out ASCII Serial Port instructions that are currently
executing or are in the queue

obtain the status of the serial port control lines

AHL

turn on or off the DTR signal

turn on or off the RTS signal

read a fixed number of characters

ARD

read a varying number of characters, up to and including the
first set of termination characters

ARL

send characters and automatically append one or two
additional characters to mark the end of the data

AWA

send characters

AWT

If you want to:

Use this instruction:

add characters to the end of a string

CONCAT

delete characters from a string

DELETE

determine the starting character of a sub-string

FIND

insert characters into a string

INSERT

extract characters from a string

MID

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