Product Features

Installing Your Modem

Using the AT Command Set

Upgrading your Modem

Modes of Operation

Dialing, Answering, and Hanging Up

Configuring with DIP Switches

Working with Memory

Controlling Result Code Displays

Controlling EIA-232 Signaling

Accessing and Configuring the Courier 56K Business Modem Remotely

Controlling Data Rates

Dial Security

Flow Control

Handshaking, Error Control, Data Compression, and Throughput

Displaying Querying and Help Screens

Testing the Connection

Dedicated/Lease Line and Synchronous Applications




Alphabetic Command Summary

Flow Control Template

Result Code Meanings and Sets

Technical Information

V.25 bis Reference


Fax Information for Programmers

Viewing LEDs

Regulatory Information and Limited Warranty


Courier 56K Business Modem Command Reference

Fax Information for Programmers

Fax Service Class 1 Commands

+FCLASS? What mode is in use Data or Fax?
+FCLASS=n (0,1,2.0) Class identification and control.
+FCLASS=? What Fax class is in use?
+FTS=n (0,255) Stop transmission and pause, 10 ms.
+FRS=n (0,255) Wait for silence, 10 ms.
+FTM=n (3,24,48,72,73,74,96,121,122,145,146) Transmit data with carrier.
+FRM=n (3,24,48,72,73,74,96,121,122,145,146) Receive data with carrier.
+FTH=n (3,24,48,72,73,74,96,121,122,145,146) Transmit HDLC data with carrier.
+FRH=n (3,24,48,72,73,74,96,121,122,145,146) Receive HDLC data with carrier.

Fax Service Class 2.0 Commands

In addition to the standard Class 2.0 fax commands, U.S. Robotics implements the following optional Class 2.0 fax commands:

+FNS=0,1 Pass-through, non-standard negotiation byte string
+FCR=0,1 Capability to receive.
+FAA=0,1 Adaptive Answer mode.
+FCT=0-255 sec. Phase C Timeout
+FHS=0-255 Hangup Status Code, read only.
+FMS=0-3 Minimum Phase C Speed.
+FBS?=500,100 Buffer size, read only.



Fax Mode Flow Control Setting

Many facsimile software products use software flow control when the modem is in Fax mode. Throughout our documentation, we recommend that you use hardware flow control for Data mode (factory setting). However, to allow compatibility with software products that use software flow control by default, U.S. Robotics fax modems automatically change to software flow control when entering Fax mode.



FCC Notice

FCC part 68, rules regarding fax operation, has been amended as follows:
Telephone facsimile machines identification of the sender of the message: It shall be unlawful for any person within the United States to use a computer or other electronic device to send any message via a telephone facsimile machine unless such a message clearly contains, in a margin at the top or bottom of each transmitted page or on the first page of the transmission, the date and time it is sent and an identification of the business, other entity, or individual sending the message and the telephone number of the sending machine or of such business, other entity, or individual. Telephone facsimile machines manufactured on and after December 20, 1992 must clearly mark such identifying information on each transmitted page.




If you want to know more about the supported Class 1 fax commands, refer to the standard for the Service Class 1 fax protocol:
TIA/EIA-578-1990 (EIA-578)
Asynchronous Facsimile DCE Control Standard - Service Class 1
November 1990 Revision: B
For more information on Class 2.0, refer to the standard for the Service Class 2.0 fax protocol:
TIA/EIA-592-1998 (EIA-592)
Asynchronous Facsimile DCE Control Standard - Service Class 2
April 1998 Revision: A
You can obtain copies of these standards by contacting Global Engineering Documents at (800) 854-7179.


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