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Modem Not Responding

Ike033197 asked
Medium Priority
Last Modified: 2010-04-12
    I have been having a probelm with my 28.8 modem for
a long time now, it just will not respond. I type "echo ATA > com4" and sometimes it gives me a error reading com4 or sometimes it just doesn't do anything. It used to work fine, and I know the modem still works. When I go inside the computer nothing LOOKS wrong, but I dont know what I am looking for. Could it be that having two internal modems and two internal hard drives is to much? If you have ANY idea please help... Thanks...
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You have to know quite a lot of information about your computer setup, but to begin you could concentrate just in the serial ports.

  You state you have two internal modems (the hard disks don't matter) , meaning that the most probably thing is happening is that you have 4 serial ports in total (2 serial ports of your machine plus the two serial ports assigned to the modems)..

  If you are not using the computer's serial ports then you should consider disable them, this could be done directly in the hardware (moving some jumpers) and in newer machinesn in the BIOS, check what is appropriate for your system.

  If you don't want or you cannot do it, then you have to check the IRQ's and Memory addresses assigned to each serial port, in newer operating systems you can assign independent IRQ and memory addresses to each serial port (W95, Linux), with others this could be not possible or bogus (Windows 3.x).

  So if you are still lost, give more information like:
-Operating system.
-How you are using each serial port.

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Com 1 & Com4 are the only two in use. I can shut down Com 2 & 3 will this help? There is not confliction between IRQ's, I checked. And I am useing Win '95? If there is anyhting else you can tell me, it would be greatly appreciated, thanks...

Could you tell me which IRQs are you using for each serial port?
Which memory address?
A complete list of all the IRQs being used in your machine could be very helpful.



   Thank you for your help so far... I checked the IRQ's and it does seem that my Com4 - IRQ7 is conflicting with my LPT1 - IRQ7 so I disabled my printer port [I really don't] need it. But I do have a question All my IRQ's are in use 1 through 15 is that a bad thing? If you still want that list of IRQ components then I can get it for you because I have one more question.  Everyhing is working fine now except it gives me a "Modem is not plugged in error", why could this be? Its internal... Thanks...


   For what you say it looks like you have your parallel port and your COM4 assigned to the same IRQ (#7), you should no do that, you have 16 IRQs and every one should be assigned to one and only one device, so my suggestion is that you disable the two COM ports you are not using and you move the IRQs of the serial ports of your modems to free ones, so you don't need to disable your prallel port. Of course if you prefer to disable the parallel port you can do it, just keep in mind: one IRQ for each device.



    Alright thanks, but about disabling the ports, should I do it through BIOS and Win '95? And will that help with the "Insert a Modem" & "Modem not plugged in" errors?

It depends on your hardware, in some machines, especially new ones, you can do that in the BIOS, have a look first there.

If the BIOS does not have any option that means you have to do it the old way: using jumper directly in the comunications card or in the motheboard when the port controller is there.

   Once they are disabled at this level W95 should detect only the ports that are enabled by the hardware.

   Is highly likely that it could solve the problems because you had two devices in the same IRQ.

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