ML1400 ASCii table confusion

JZerb

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Oct 2016
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so im setting up a panel mount printer over CH0 on a Micrologix 1400 and im a bit confused as to why its doing what its doing with the ASCii commands. If i hook the PLC up to my PC and use RealTerm, send the AWA command from the PLC, i get the string that should come through along with a CR and LF. I send it again, and it does indeed go down a line and send the same string again. The termination characters that i have setup in RS500 for that channel are default at \d and \ff, but when i look at the ASCii table in the ML1400 manual i see that CR should be equal to get 0D and LF should be equal to hex 0A. Could someone un confuse me here? because it seems to work like it should, but i dont understand how or why.
 
See this thread for some good explanation:
http://www.plctalk.net/qanda/showthread.php?t=65250

With ASCII transmission, each character is a single byte which can be represented as a two-digit hex value. Some of these characters cannot be displayed as single digit glyphs, so the programmers come up with code systems to represent the nonprintable characters. RSLogix happens to use \d, \a, \ff, etc. for its termination and append characters. These codes aren't the actual data that's sent, but they tell the software to substitute the actual ASCII character such as carriage return or line feed. To add to the confusion, for some reason RSLogix uses a totally different system to display nonprintable characters in string data--a control character which consists of a caret and letter.
 
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