🚀 go-pugleaf

lubkt@synergy.CC.Lehigh.EDU (Binod Taterway) writes:

>Q: How do you find IRQ levels of COMx ports other than trying both 4
>and 3? Traditionally, this has been 4 for COM1 and 3 for the rest.
>Lately I have found a lot of vendors to violate this standard.

Traditionally, IRQ4 is shared by COM1 and COM3, IRQ3 is shared by COM2 and
COM4; although I've heard of IRQ5 being used for COM ports >2 also.
Some modems and serial cards I've seen allow independent setting of the 
IRQ# and COM#; i.e. it is possible to assign IRQ3 to COM1.

Some modem manufacturers include a little program typically named
"COMTEST.COM" with their product.  Its purpose is to identify the ports
you already have that are in use, to allow you to find a free IRQ.  I
think some rat makers use it too, and some others with peripheral boards
(e.g. hand scanner interfaces) that need an IRQ.  Some BBS somewhere ought
to be able to provide this to you.

-JTT