Configuring Your Modem

Choose the highest asynchronous serial speed both modem and computer can support.

Enable error correction. If possible, choose CCITT V.42 for compatibility with CCITT V.42bis data compression.

Enable data compression. HP recommends CCITT V.42bis for higher maximum compression ratios and handling of precompressed data streams.

Enable flow control. Use hardware instead of software flow control if possible.

Use default modem parameters for purposes outside PPP protocol, including other inbound applications

Set up dialers for UUCP or PPP outbound connections. Dialers' PPP-specific register settings ensure that a general purpose modem used for PPP will work as intended during an PPP session.

Allow bidirectional connections over any available modem. Try the following suggestions to configure bidirectional modems and to allow modem use by other applications, such as uucp, tip, cu and remote logins:

Set S0 register value to 1 to answer after one ring.

Lock the DTE interface to the selected speed. Many modems do not support a speed register, but you can store the current value with the &W command

Disable modem printing of result codes when processing incoming calls. You may have to disable result codes too. Start the dialer with ""ATE1 or its equivalent.

Set the modem to print extended result codes, like Busy, when dialing out. Better dialer performance is possible. Enter this in the /etc/ppp/Dialers file, if necessary.

Set the modem so it only asserts the Carrier Detect (CD) signal when the carrier is established with another modem

Set the modem to disconnect the call and restore its saved values when the computer deasserts the Data Terminal Ready (DTR) signal