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Rockwell Automation 1785-Lxxx Enhanced and Ethernet PLC-5 Programmable Controllers User Manual

Page 170

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Publication 1785-UM012D-EN-P - July 2005

10-20 Communicating with Devices on a Serial Link

Delete mode

Select how the controller responds to
a delete character.

Select Ignore, CRT, or Printer. If you select Ignore, the controller ignores
the delete character. If you select CRT or Printer, the controller ignores the
character it received immediately before the delete character. The
controller then sends a signal to the CRT or printer to erase the deleted
character. Select CRT or Printer only if you enable the echo mode.

XON/XOFF

Whether or not you want XON/XOFF
enabled

As the controller receives characters, it constantly determines how many
more it can receive without losing any. When XON/XOFF is enabled, the
controller sends a “stop sending character,” XOFF. If the sending device
has the XON/XOFF feature, it stops sending characters. When the
controller has more room, it will send a “start sending” character (XON).

Select ENABLED or DISABLED.

Echo

What the controller should do when it
receives an ASCII delete character

If you disable the echo mode, characters received by the controller are
sent only to the echo counter and not to an output device, such as a CRT
or printer. If you enable the echo mode, the controller sends any
characters it receives through an ASCI read or read line instruction to a
waiting output device. For example, if you want the controller to print a
message to a LED marquee, enable the echo mode.

Termination 1
Termination 2

The termination characters you
defined

Enter a maximum of two characters (hexadecimal).

Use termination characters with the ASCII Read Line instruction or with
the Test Buffer for Line (ABL) to indicate a line has been entered.

The default character is the ASCII equivalent for [RETURN], 0x0D. You
can also use the ASCII equivalent for LINE FEED (0x0A). To specify no
character, enter \FF.

Append 1
Append 2

The append characters you defined

Enter a maximum of two characters (hexadecimal).

Use append characters with the ASCII Write with Append (AWA)
instruction to indicate the end of a line. Append characters are the last
characters sent after a line of information.

The default characters are the ASCII equivalent for [RETURN] (/0D) and
LINE FEED (/0A). To specify no character, enter \FF.

This Field

Specifies

Configure by Doing the Following