3Com DIGITAL MODEM User Manual

Contents

Using the Phone Out Port 2-17Placing Analog Modem CallsTo place a call from your PC or Macintosh using the optionalV.32bis 14.4 Kbps internal analog fax modem (included withmodels 3C872 and 3C877), use the AT command ATDT (forconnection to an analog modem using touch-tone dialing) orATDP (for connection to an analog modem using pulse dialing).Using Communications Software to Place CallsIf you are using standard communications software, select aHayes-compatible modem configuration and dial outthrough the 3Com Impact digital modem. Refer to yourcommunications software documentation for more details.Receiving Data CallsIncoming circuit-switched data calls from other3Com Impact digital modems or from ISDN devices andSw56 equipment may be received by the digital modem.If auto answer is disabled (the default) in register S0, a RINGmessage is delivered to the Computer port upon reception ofan incoming data call to the digital modem. The command ATA answers the incoming data call. A CONNECT message is thendelivered to the Computer port upon successful connection.If auto answer is enabled, the call is automatically answeredand a CONNECT message, indicating the speed of theconnection, is delivered to the Computer port.Using the Phone Out PortIf you have analog touch-tone telephones, answeringmachines, fax machines, external analog modems, or otheranalog telephone devices, connect them to the 3Com Impactdigital modem’s RJ-11 modular jack labeled Phone Out onthe digital modem’s back panel (see Figure 2-1).The 3Com Impact digital modem does not support pulsedialing (rotary) telephones.