Browse Prior Art Database

Integrated Cellular Modem Commands for Control of Data and Voice Operation

IP.com Disclosure Number: IPCOM000106593D
Original Publication Date: 1993-Nov-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 4 page(s) / 122K

Publishing Venue

IBM

Related People

Hendershot, DR: AUTHOR [+2]

Abstract

Described is a software implementation to provide 'AT' commands to enable cellular modem devices to be integrated with personal computer (PC) workstation operation. The commands provide control of the power output, transfer protocols for error correction, voice-to-data and data-to-voice switching, and other unique cellular functions.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 41% of the total text.

Integrated Cellular Modem Commands for Control of Data and Voice Operation

      Described is a software implementation to provide 'AT' commands
to enable cellular modem devices to be integrated with personal
computer (PC) workstation operation.  The commands provide control of
the power output, transfer protocols for error correction,
voice-to-data and data-to-voice switching, and other unique cellular
functions.

      The integrated cellular modem commands are 'AT' commands to
provide the control and implementation of cellular modem operation
for use as a PC based integrated modem.  The commands are
non-standard modem commands that enable cellular radio modems (CRMs)
to provide the capability of executing extensions to standard
commands and cellular specific commands.

      For extensions to standard commands, the following are required
for standard Hayes AT type command sets:

o   Dialing - Used to indicate that a call is to be made on a
    cellular connection where the dial modifier '!' has been added to
    the standard 'ATD' command.  Therefore, a cellular call to
    555-1234 would be dialed using 'ATD!5551234' command.  If DTMF
    tones are to be included in the dial string, they would be
    preceded by the 'T' dial modifier, such as 'ATD!555123t4567'.
    The '!' dial modifier is only valid when the CRM is off-line and
    when it is the first character in the dialing string.

o   Default Dial Command - Bit 5 of S register 14 is normally used to
    define the default dialing mode, such as 1 = Pulse mode, 0 = Tone
    mode.  In order to accommodate cellular dialing, bit 6 is now
    used to indicate 0 = Telco, 1 = Cellular.

      The concept implements new commands in order to interrogate the
cellular telephone.  All of the new commands begin with 'AT!' and all
commands and responses are terminated with a carriage return (HEX
'OD') character.  All parameters and return values are ASCII coded.
The following fifteen new commands are provided for the interrogation
operation:

1.  AT!C  Report Air Charge Data - The air charge data is reported by
    this command.  'n = 0' for charge rate, hp2.'n = 1' for the Roam
    accumulated air charge, 'n = 2' for total accumulated air
    charges.

                    FORMAT:      AT!C<OPTIONS>
                    RESPONSE:    <Air Charge Data> or ERROR if not
ETACS

2.  AT!P Enter Debug Mode - This command places the CRM into debug
    mode.  The CRM will remain in debug mode until terminated by the
    '+++' escape sequence, when an OK will be returned to the DTE and
    the CRM will return to the command mode.

                    FORMAT:      AT!P
                    RESPONSE:    OK

3.    AT!F  Perform Internal Test - This command instructs the CRM to
    perform any defined internal test commands that are contained i...