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Chapter 9: Operation
also have an error-checking modem for your PC or terminal.
To install the external modem:
1. Power up and set the modem according to the manufacturer's instructions.
2. Connect the external modem to ISACC's RS232 serial port.
3. Connect the phone line. This can be done one of two ways:
a. Hook up the phone line directly to the external modem. If you do this,
you cannot use dialing modes 0-4 (see Chapter 7). Also, you cannot call into
ISACC for a voice mode status report. ISACC will only have access to the
phone line through the external modem.
b. Split the phone line. Hook one wire to the external modem. Hook the
other wire to ISACC. This set up will allow you to use all dialing modes.
NOTE: When calling in to ISACC with the split phone line, the external
modem will answer first. To bypass the external modem, hang up and call
back. On the second call you will access ISACC's phone interf ace.
4. Program one or more of ISACC's dialout phone numbers to dialing mode 5.
See Chapter 7, Phone programming.
5. Reset ISACC. This initializes ISACC so that it knows that an external modem
exists.