Rockwell Automation 1771-DA,D17716.5.13 U MNL 1771-DA ASCII I/O MODULE - Manual (Page 60)

Choosing Module Features
Chapter 3
3Ć18
Record the 7-bit ASCII code in binary or hex for the end-of-string
delimiter in IW3(10-16) using the form (found at the end of this chapter)
or the boxes on the next page.
IW4
End-of-String Delimiter
17 16 15 14 13 12 11 10
0
String length is the maximum number of characters that your ASCII
module can transfer as a unit from the ASCII device to the processor data
table. You set the string length to match that of your ASCII device (data
mode), or according to your message requirements (report generation
mode) up to the maximum that the module can handle. The maximum
number of characters that your ASCII module can handle as a string
depends on the module’s mode of operation. In data mode, the module can
handle a string of up to 62 characters per block transfer. In report
generation mode, the module can handle a string of up to 999 characters,
transferred over several block transfers.
The string of characters sent from the device to the module can be fixed or
varied in length. Refer to the specifications of your ASCII device. Some
ASCII devices generate the same string length for each transfer by adding
fill characters, described later, when the amount of data in each transfer
varies. The device adds fill characters and an end-of-string delimiter at
the end of each message (Table 2.J).
Setting String Length,
IW2(00Ć13)