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CHAPTER 6: Troubleshooting
If both modems exchange carrier signals but fail to establish a data communications
link...
• Place the call again. You may have had a bad phone line or a bad
connection. The telephone company routes all calls, even local calls,
differently each time you call.
• Call a different modem to see if the problem persists. The problem
may be with the modem you first tried to call.
• The remote modem might be an older 2400-bps modem that does not
support error control. Disable error control by going into terminal mode
(your communications software should let you switch to terminal mode)
and:
1. Type
AT&M0
(the last character is zero)
2. And then press the ENTER key.
3. Try connecting with the remote modem again.
4. When the call is finished, remember to reset the modem
by typing
ATZ
and then pressing the ENTER key.
6.2 During Data Transfer
If your screen displays random or garbage characters...
• Set your software to the same word length, parity, and stop bits as the
remote modem.
• Make sure that your software and modem are set to the same flow-control
setting and to either a fixed or variable serial-port rate.
• Load the template that enables hardware flow control as well as other
optimal settings. Go into terminal mode (your communications software
should let you switch to terminal mode) and:
1. Type
AT&F1
2. And then press the ENTER key.
• Disable any Terminate and Stay Resident (TSR) programs running in the
background.