User guide

Developers guidelines | AT commands
338 June 2010
Glossary
3GPP
3rd Generation Partnership Project. http://www.3gpp.org
Analog
An analog signal can have any value between two limits. For example, traditional
telephone lines transfer the human voice, itself an analogue signal, by means of a
continuously varying electrical voltage. This voltage is an electrical representation of
the pressure produced by the sound on the telephone microphone.
ASCII
Acronym for American Standard Code for Information Interchange. A standard code
used for transferring data between computers and associated equipment.
Asynchronous communication
Data communication in which data elements are NOT separated according to time.
Instead, a special code such as a start bit and a stop bit is used. By using a code, in
lieu of time, asynchronous communication is more tolerant of time variations and
complex timing circuits are not needed. The serial port and the COM port of a
computer are associated with asynchronous communication, as is the RS-232-C
interface. Also some end to end modem protocols are asynchronous.
AT
Abbreviation for Attention and tells the phone modem that a command follows. AT
must be used at the beginning of a command line or dial string.
AT command set
The set of commands used to control the modem.
Auto-answer mode
The state in which the modem automatically answers the telephone when it rings.
Beam
Sending an item to another phone or a compatible application using the infrared link.
This can include ring signals, calendar entries and business cards.
Bearer
The method for accessing WAP from the phone, for example GSM Data (CSD) and
SMS.
Bluetooth
Secure, fast, point-to-multipoint radio connection technology.
http://www.bluetooth.com
bps
Acronym for ‘bits per second’ (bits/s). A measure of speed at which bits are
transmitted over the telephone lines.
BTHF
Bluetooth Handsfree