Allen-Bradley MicroLogix 1200 Reference Manual page 278

20-10 ASCII Instructions
Publication 1762-RM001C-EN-P
When using this instruction you can also perform in-line indirection. See
page 20-29 for more information.
Entering Parameters
Enter the following parameters when programming this instruction:
• Channel is the number of the RS-232 port, Channel 0. (For the
1764-LRP only, you can select either Channel 0 or Channel 1).
• Source is the string element you want to write.
• Control is the control data file. See page 20-6.
• String Length (.LEN) is the number of characters you want to write
from the source string (0 to 82). If you enter a 0, the entire string is
written. This is word 1 in the control data file.
• Characters Sent (.POS) is the number of characters that the controller
sends to an external device. This is word 2 in the control data file.
Characters Sent (.POS) is updated after all characters have been
transmitted.
The valid range for .POS is from 0 to 84. The number of characters
sent to the destination may be smaller or greater than the specified
String Length (.LEN) as described below:
– Characters Sent (.POS) may be smaller than String Length (.LEN) if
the length of the string sent is less than what was specified in the
String Length (.LEN) field.
– Characters Sent (.POS) can be greater than the String Length
(.LEN) if the appended characters or inserted values from in-line
indirection are used. If the String Length (.LEN) is greater than 82,
the string written to the destination is truncated to 82 characters
plus the number of append characters (this number could be 82,
83, or 84 depending on how many append characters are used).
• Error displays the hexadecimal error code that indicates why the ER
bit was set in the control data file. See page 20-30 for error code
descriptions.
Addressing Modes and File Types can be used as shown below:
Table 20.8 AWA Instruction Valid Addressing Modes and File Types
For definitions of the terms used in this table see Using the Instruction Descriptions on page4-2.
Data Files
Parameter
Channel
Source
Control •
(1) The Control data file is the only valid file type for the Control Element.
(1)
Function Files
•
Address Address
Mode Level
• •
• •
• •