
5 Troubleshooting
Check for loose connections between the modem and the computer, the phone jack, and AC power.
You might have had a poor connection because of line conditions or the problem might have originated on the other end of the line. Try again.
If you were online with a BBS or an online service like CompuServe, it might have hung up on you because of lack of activity on your part or because you exceeded your time limit for the day. Try again.
The Modem Cannot Connect When Answering
The default DTR Control command (&D2) inhibits autoanswer. To enable autoanswer, change the DTR Control to &D0, and make sure &Q0, &Q1, &Q5, or &Q6 is also set. For more information, see the &D command in Chapter 4. For information on changing the modem’s default configuration, see Chapter 3.
Autoanswer might be disabled. Turn on autoanswer in your data communications program or send the command ATS0=1 (ATS0=2 if you have Caller ID service) to your modem in terminal mode.
File Transfer Is Slower Than It Should Be
You might have an older UART. For best throughput, install a 16550AFN UART or a
If you are running under Windows 3.1 and have a 16550AFN UART, you must replace the Windows serial driver, COMM.DRV, to take full advantage of the UART’s speed.
If you are using a slow transfer protocol, such as Xmodem, try Zmodem or Ymodem/G instead.
Is your line noisy? If there is static on your line, the modem has to resend many blocks of data to insure accuracy. You must have a clean line for maximum speed.
Are you downloading a compressed file with MNP 5 hardware compression enabled? Since hardware data compression cannot compress a file already compressed by an archiving program, the transfer can be marginally slower with data compression enabled than with it disabled.
Does your Internet service provider (ISP) use the same 56K protocol as your modem? The default setting of your modem is to connect using either the K56flex or the V.90 protocol, depending on which one the ISP modem is using. If your ISP uses the X2 protocol, the maximum speed you will be able to connect at is 33,600 bps. Check with your ISP to see which protocols it supports, and check the
Try entering the &V1 command to display information about the last connection, making a screen print of the connection statistics, and checking for parameters that might be unacceptable.
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