ZyXEL U-1496S Plus User Guide - Page 76

Assume using a cellular phone data interface adapter, the following figures illustrate three installation examples. Fig 13-1 is an example of a mobile phone that has a handset cradle and separate transceiver and handset. Fig. 13-2 is an example of a mobile phone that has a separate transceiver and handset. Fig. 13-3 is an example of a one-piece hand-held mobile phone. Chapter Fourteen - FAX OPERATION The U-1496 series universal modem supports the Group 3 send and receive facsimile function. You must connect the modem to a computer, usually a PC, in order to use this fax function. The computer is the input/output device for the fax function. The interface between the modem and the computer is the normal RS-232 serial connection. It uses the same interface for both data and fax applications. In fax operation, the modem does the function of protocol handshaking and image data transfer, and the computer does the job of image data creation, capturing, conversion, compression, decompression, retrieving, and storing. On the disk a fax program for PCs is always included. The documentation for this program can be found in a file on the disk. Please refer to that documentation for the latest developments. Some distributors and dealers also include other software with the modem. Refer to the accompanying documentation - printed or on disk. In the following sections, we will describe the CCITT T.30 fax protocol, the fax commands, status report result codes, flow control protocol, and fax applications. The instructions for using the accompanying modem/fax/voice utility program are contained in the document file in the software disk. Please refer to the updated document disk file for software usage instructions. THE CCITT T.30 FAX PROTOCOL The CCITT T.30 fax protocol describes the G3 fax handshake signals and procedures. The U1496 series modem takes full control of this protocol, initiates and terminates fax calls, manages the communication session, and transports the image data. The modem shields the computer fax software from the T.30 protocol handling. Along with T.30, the U-1496 series modem provides the highest fax speed up to 14400 bps using the new fax transmission standard V.17. When connecting to an existing non-V.17 fax device, the modem provides a highest speed of 9600 bps and will automatically fall back to 7200, 4800, and 2400 bps if the line quality is not good enough. When connecting to a higher speed and better performance V.17 machine, 14400 bps transmission speed can be achieved. It will fall back to 12000, 9600, or 7200 bps if the line quality is not good enough. THE FAX COMMAND SETS The U-1496 series universal modem supports two command sets for the fax function, the EIA PN 2388 Class 2 command set, and the Extended Fax AT command set. We will briefly describe the supported Class 2 commands here. Please refer to the EIA document for detailed explanation. All of the following sections are related to Extended FAX AT commands. THE CLASS 2 COMMAND SET The following class 2 commands are supported and implemented per EIA PN2388 (8/20/90). Command Style