Way to detect installed serial ports?

[BobTheMad]

What would be the best way to go about detecting the number of serial ports that a PC presently has? I have some older assembly routines that can tell me, but they seem to lock up some of the newer PC's that I have tested it on.

Thanks! Thought for the day: Beware of Gods who cannot laugh...

 

[agual]

Try this:

DEF SEG = &H40
PRINT "Address of COM1": PEEK(0) + 256& * PEEK(1)
PRINT "Address of COM2": PEEK(2) + 256& * PEEK(3)
PRINT "Address of COM3": PEEK(4) + 256& * PEEK(5)
PRINT "Address of COM4": PEEK(6) + 256& * PEEK(7)

If the address displayed is 0, the port does not exist, or is not installed for DOS. Antoni

http://www.geocities.com/antonigual/index.html

 

[BobTheMad]

That seems to be working. Follow-up question... Is there a FAQ or document that has a list of what all the addresses point to (if I wanted to check parallel ports or anything else for example)

thanks! Thought for the day: Beware of Gods who cannot laugh...

 

[qbasicking]

Brown's Interrupt list