COM Ports & Serial Connections

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Is anyone else having problems witht he Polaroid PDC 700 ? I have a modem and a serial mouse, and got an adapter [9 to 25 pin]. So far so good, but the problem is that PhotoMax keeps saying "Connection Failed". Anyone can help ? COM 2 & 4 are assigned the same IRQ but for some reason Windows won't let me change that. I have a P166 and it doesn't have USB support so I can't get a USB Port and a USB mouse. THe only PS/2 plug is in use by the keyboard and I couldn't find any ports with PS/2 plugs for sale, so I can't buy a PS/2 mouse either. Please someone help me, I'm gonnna go nuts !

-- Pedro Souza (ph@highway.com.br), September 09, 1999

Answers

I don't know anything about your camera and software, but I'll try to help with the Serial I/O part of your question. Com1 and Com3 normally share an interrupt, as do Com2 and Com4. The interrupt is set by jumpers or switches on the I/O boards, or by settings in your computers BIOS setup. Windows does not have control over these settings. Also, many computers cannot use Com4 due to conflicts with certain video card capabilities. The other item to consider is that you (generally) cannot use Com1 and Com3 at the same time, and you cannot use Com2 and Com4 at the same time. This is because of the interrupts being the same.

What I would do if I were you is to set your modem to use Com1, your mouse to use Com2, and let your camera/software use Com3. Then you are free to use your mouse with either the modem or the camera (no conflicts). Just be aware that you probably won't be able to use your modem at the same time as you are transferring files from your camera.

Dave

-- Dave Schambach (DSchambach@Compuserve.com), September 10, 1999.


I suggest to change the modem setting to Com 3 & IRG 5 (unless if your sound card uses IRQ 5 and must use it). Also not all modems could be configured by user. Modems such as USRobotics Sportster could be set up at Com 3 IRQ 5, and in this case Com 1 is IRQ 4, Com 2 is IRG 3, and there is no IRQ conflict. Some sound cards even if are using IRQ 5, after another device assumes that IRQ, could easily be changed to another available IRQ (depends on type of sound card you have). I am using configuration of two Com Ports with standard IRQ (4&3)and Modem as Com 3 IRQ 5 among more than 100 PCs without any problem. Good Luck.

-- Fred (tabarrok@frontiernet.net), September 10, 1999.

If the prior assistance hasn't helped...

Do you have Plug-n-Play cards in your system? If you have several, and one of them is your COM adapter, Windows assigns interupts in the order of their cards original insertion.

Remember, this is for PnP. I had to do this because the software supplied by Sony was not flexible enough to allow me to enter what Windows had assigend.

I had to do this... REMOVE the PnP cards from your system (power it up so it knows they are gone). Insert the COM adapter first and configure (power up). Look at the device in the system device list, you should now see that standard interupts and addresses are assigned. Try your software. Install the other PnP cards to return to your normal configuration.

(if nothing else has helped, this is just another idea.)

-- ted (commanderted@yahoo.com), September 15, 1999.


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