15-2CHAPTER 15: TROUBLESHOOTING

Make sure that verbal result codes (status messages) are enabled. Send these commands to the Business Modem:

For your modem to

Command

 

 

enable message display

ATQ0

 

 

Display verbal messages

ATV1

 

 

Review your communications software manual to see what Carrier Detect (CD) operations your software requires. Then see the chapter about Controlling EIA-232 Signaling.

Although it is a rare condition, check whether your computer is reversing the send/receive functions at the EIA-232 interface. Refer to your computer's documentation.

Check your RS 232 cable to make sure it is not a NULL modem cable.

The Business Modem won't dial

You may need to change the DTR setting at the Business Modem. If so, see the chapter about Controlling EIA-232 Signaling.

Make sure that the phone line from your wall jack connects to JACK port of the Business Modem.

Make sure the Business Modem is connected to a standard analog phone line and not to a digital system (typically found in offices and hotels).

If the Business Modem responds NO DIAL TONE when you attempt to dial, first make sure that the phone line is connected to the JACK port on the back of the Business Modem.

If you hear dial tone when the Business Modem tries to dial but, it quickly returns off hook and reports NO DIAL TONE, try adding X5 to the dial string, for example sending ATDTX5 5551212. The Business Modem will ignore dial tone detection.

Page 126
Image 126
3Com 56K manual Business Modem wont dial, For your modem to Command Enable message display, Display verbal messages