View Full Version here: : Serial port wont work
allan gould
18-04-2008, 03:18 PM
I have a problem that I cant seem to work out. When my wife was writing her PhD I bought her a laptop that had fast drive, memory etc and 3 USB ports as well as a serial and parallel port on the machine. I was thinking Id use it later for astonomy.
But I cant get the serial port to work at all. I look in device manager and the serial port is there and it says its OK but when I try to use it (update Synscan software or communicate using a planetarium program), she not work. Ive gone into the BIOS and set the port to auto but still no deal.
Any really computer savy people out there that can help? Im totally stupid as far as this goes and Im more a danger to myself than anything.
I must say that to run a planetarium prog or update Synscan software I use an older laptop and the serial port on that is fine.
Regards, Allan
Hi Allan,
It's a while since I have dealt with serial ports, but sometimes you need to go into windows and match the settings of the port with the settings of the app with respect to baud rate, stop bits etc. Also check which com port the app is trying to connect on, com1, com2 etc and adjust accordingly.
Sorry, not much help.....
Paul
Babalyon 5
19-04-2008, 02:37 AM
I would give what the previous poster has suggested a go, but I must admit that I use a USB to Serial adapter, which poops on the ports on the machine and functions very well.:D
Hi Allan.
A long, long time ago I had problems with a serial port, and it turned out there was some other application "using" the port. It wasn't using it in the sense of doing something, but waiting for something to happen (like a terminal emulation program waiting for signals to appear on the serial port or a modem to be connected). Since this program had control of the port, no other program could access it. It drove me nuts until I found out which process was doing it, and stopped it from loading. I can't remember what it's name was now, but I'd go through the list of processes in task manager, and see if any likely program is there.
Good luck.
Noel
allan gould
19-04-2008, 06:05 PM
Thanks for all your assistance. I have a usb to serial adapter but they are not a real serial port. I will try you suggestions and see hat is going on.
Allan
Maverick
19-04-2008, 07:18 PM
Hi Allan!
If you can check IRQ settings in device manager.Usuly COM1 is using IRQ4 and COM2 IRQ3.Maybe you have conflict in IRQ's.If you open Control Panel , System , Hardware Tab , Device Manager , select View , Resources by type , Interrupt Request.COM1 and COM2 shouldn't clash with other IRQ's.
If they are double click on port with same IRQ as COM1 or 2 , on resources tab remove tick on automatic settings and manualy set IRQ.
Use numbers not used by IRQ's ,(5 , 7 , 11 or other).Complicated;)
Hope it's that.;)
allan gould
21-04-2008, 08:52 AM
Hi
Had a go at this over the weekend and almost made my brain melt down. Investigated every setting possible but no go. Eventually I'd fiddled with it so much that I could not get my USB to serial connector to work at all, even after reinstalling all the software. Eventually I switched off the serial port (Com1) in the BIOS and got back my COM4 port working normally. Strange as the device manager said there were no conflicts but thats Windoze for you.
NO MORE FIDDLING FOR ME. I'll leave well enough alone.
ABut thanks for your help guys - much appreciated.
Allan
Dennis
21-04-2008, 09:17 AM
Hi Allan
I have a very old Dell Latitude CPi with Windows 98 2nd Edition and after a BIOS update, the Serial port failed to function. I rolled back the BIOS to a previous version and it worked again. This was some 5 or 6 years ago.
Cheers
Dennis
Give it to some kid to fiddle with, you know what they're like.....
Cerberus
21-04-2008, 01:59 PM
before you do something drastic, like re install windows, i would uninstall any program/driver that uses com ports, on my previous pc i bought a bluetooth usb dongle and after i installed the driver software it messed everything up. also this may sound obvious, but are the com ports(sometimes known as legacy) enabled in bios?
allan gould
21-04-2008, 04:10 PM
Got my USB2serial interface working again si I'm not fiddling with anything. Thanks for all the help
Allan
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