> I have only this modem using serial ports. My mouse is a PS/2 mouse.
> The modem documentation specifically mentions that COM2 is the
> recommended port to connect to under Windows, for reasons beyond my
Ya got me. Doesn't make sense to me either. A PS/2 mouse normally uses
IRQ 12, so it shouldn't conflict with either serial port.
I've been using external modems at various speeds on COM1 for over 5
years now with DOS, OS/2, Win 3.1, Win95, WinNT and Linux, and haven't
had a problem with any of them
If you've got an old serial interface with 8250 UART chips, you may have
serious problems running the port faster than 9600bps, but you'd need a
really old system to have that problem today. Every Pentium-or-better
motherboard with built-in serial ports I've ever seen has 16550AFN (or
compatible) serial ports, which are reliable at 115200bps (where most
56K modems like to run at.)
Quote:> The motherboard I'm using is an Intel one with built in sound
> card. Could that be the reason?
You'll have to find out what interrupts and ports the sound card is
using. If it's a clone of the Creative Labs SoundBlaster, the factory
defaults will be:
Digital Sound I/O port: 0x0220 - 0x022F
MIDI UART I/O port: 0x0330 - 0x0331
FM Synthessi I/O port: 0x0388 - 0x038B
Low-DMA channel: 1
High-DMA channel: 5
You will want to make sure to change the IRQ to something else, since 7
is used by your printer interface. This IRQ sharing works OK under DOS
and Windows only because those platforms don't normally use the IRQ when
printing to the parallel port.
The standard resources used by serial ports (so you can check for
COM1: port 0x03F8-0x03FF, IRQ 4
COM2: port 0x02F8-0x02FF, IRQ 3
There are no official standard assignments for COM3 and COM4, but these
are often used:
COM3: port 0x03E8-0x03EF, IRQ 4
COM4: port 0x02E8-0x02EF, IRQ 3
Note, that these definitions cause conflicts between COM1/COM3 and
between COM2/COM4. This can cause problems. Making sure that you use
other IRQs for the extra ports will prevent those problems.