Multi-Tech Systems 7500 User Manual

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TECHNICAL NOTE
Modem AT Commands
This technical note outlines compatible AT commands that may be used with ION 
meters equipped with the internal modem option.  AT commands control a 
modem’s operation and are useful for setting up the modem (for example, if you 
want to turn off the modem’s autoanswer feature).  All AT commands begin with 
the characters AT, which is short for “attention code”.  This is what alerts the 
modem that a command is following immediately.
C
AUTION
Adding, removing or changing AT commands should only be performed by qualified individuals.  Putting
improper code  in the modem configuration string could cause the modem to become inoperable.
Depending on the ION meter and its date of manufacture, the installed optional 
internal modem could be one of two different brands.  The Conexant modem is the 
older type modem, and is available in North American (FCC approved) or 
European (CTR-21 compliant) versions.  The newer modem is manufactured by 
Multi-Tech and is a universal modem that can be readily used in most countries, 
and complies with FCC, Industry Canada and TBR-21 regulations.
Contained in this document is a section explaining how you can determine which 
type of modem is installed on your ION meter, a section that lists AT command 
sets for the new (Multi-Tech) modem, and a section that lists AT command sets for 
the older (Conexant) modems.
In This Document