ΙΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ» Ί Ί Ί GENERAL MODEM TROUBLESHOOTING: PART 1 Ί Ί Ί ΘΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΌ The following information can help you solve certain problems with your Intel product. "(Field report)" means that the information comes from a customer and may not have been verified by Intel's compatibility lab. ARE YOU ON A PBX PHONE SYSTEM? If your modem loses data or has degraded performance, it could be because it's connected to a PBX telephone system. Check with the phone company to determine if you're connected to a PBX or other phone system that requires a special digit to dial out. CARRIER ALREADY ESTABLISHED MESSAGE If you receive this message before the modem dials the phone number, use a communication program or TESTCOM to change the values of Data Carrier Detect (DCD) and Data Terminal Ready (DTR). Intel sets these signals to 0 on non-MNP modems (2400B Calssic, 2400EX, and CCP Modem Option) to match the Hayes default, but many communication programs require a value of 1 to work. The 2400B Classic MNP, 2400EX MNP, and 9600EX If you use TESTCOM, select 6 from the main menu. This allows you to use the Hayes command set to address the modem hardware. You can also enter the following line at a place in your modem software that responds to the Hayes AT Command Set: AT&C1&D2&W The C1 changes the DCD to 1, the D2 changes the DTR to 2, and the W writes the information into modem memory. DETECTING PORTS WITH DEBUG If you're having a problem determining which parallel and serial ports your computer is using, you can check for the I/O ports using the DEBUG program. Follow these steps to use DEBUG: 1. At the DOS prompt, type DEBUG and press Enter. 2. At the DEBUG prompt (a dash), type D 40:0 and press Enter. This displays the hexadecimal codes of the active I/O ports, first serial then parallel: 0040:0000 F8 03 00 00 00 00 00 00-BC 03 00 00 00 00 00 00 This display indicates one serial port installed at 3F8 and one parallel port installed at 3BC. (Note that the high and low bytes are reversed.) ΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ 1/91 Intel FaxBack # 4460 Page 1 ΙΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ» Ί Ί Ί GENERAL MODEM TROUBLESHOOTING: PART 1 Ί Ί Ί ΘΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ (continued) ΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΌ 3. To quit DEBUG, type q and press Enter. INTERMITTENT SWITCH TO COMMAND MODE If your modem intermittently switches to Command mode after connecting with a remote system, change the DTR option to &D2 with this command: AT&D2 LEASED LINE SETUP If modems fail to communicate over leased lines, but work fine on standard lines, change the &L setting to &L1. The default setting is &L0. See your modem command guide for more information. In addition, if the leased line is a 4-wire line rather than a 2-wire line, a 4-wire to 2-wire converter will be required. This converter is often a simple switch on the leased line telephone equipment in your office. MODEM DIALS BUT DOES NOT CONNECT Communications software has each of the COM ports configured for a specific I/O address and IRQ combination. If the modem and software configurations do not match exactly, the modem may dial but be unable to signal the computer that it has achieved a connection. Compare your modem I/O and IRQ settings to those in your software to ensure an exact match. This problem may also appear when there is another device using the same IRQ as the modem. Adjust the modem and conflicting device to different IRQ settings so they no longer conflict. NO DIALTONE MESSAGE Some computers (typically mainframes) require that modems call once, hang up, wait for a return call, and then call again (using ATD). With 2400B modems, when the modem picks up the phone to dial the second time, it detects no dialtone and hangs up. To avoid the problem, type this command: ATX3&W then press Enter. This suppresses the NO DIALTONE result code allowing the modem to connect. ΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ 1/91 Intel FaxBack # 4460 Page 2 ΙΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ» Ί Ί Ί GENERAL MODEM TROUBLESHOOTING: PART 1 Ί Ί Ί ΘΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ (continued) ΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΌ PHONE LINES ATTACHED CORRECTLY? Your modem won't work if the phone lines are connected incorrectly to the back of the modem. The connector marked "line" for the phone line coming from the wall, and the one marked "phone" is for the phone line going to the telephone. Neither the computer nor the modem need to be turned on to use the phone for normal voice calls. ΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ 1/91 Intel FaxBack # 4460 Page 3