Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!ames!pasteur!ucbvax!janus!brand
From: brand@janus.uucp (Graham Brand)
Newsgroups: comp.sys.ibm.pc
Subject: COM ports - I am still confused!!!
Message-ID: <29697@ucbvax.BERKELEY.EDU>
Date: 15 Jun 89 22:33:50 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Reply-To: brand@janus.UUCP (Graham Brand)
Organization: University of California, Berkeley
Lines: 31

In article <2073@iesd.dk> kjeld@iesd.dk (Kjeld Flarup) writes:
>I have noted some questions concerning interrupts and COM ports.
>First there is a reply to Dave Vasko:
>		PORT    ADDRESS      INTERRUPT 
>		COM1	3F8-3FF      IRQ4
>		COM2	2F8-2FF      IRQ3
>		COM3    2F0-2F7      IRQ4 ( or IRQ2 )
>		COM4    3F0-3F7      IRQ3 ( or IRQ5 )
>
>I think. because noone seems to know for sure.
   ^^^^^

	Thanks for the useful information, assuming that it is correct! 
However, previous responses have left me a little confused, I must 
admit. For example, I have seen the following references to port 
addresses:

(foss@iris.ucdavis.edu)
3E8 for COM3
2E8 for COM4

(simon@ms.uky.edu)
0040:0000 for COM1
0040:0002 for COM2
0040:0004 for COM3
0040:0006 for COM4

These seem different to me! Would someone please enlighten me?

Cheers,
-Graham Brand (brand@janus.berkeley.edu or ..!ucbvax!ucbjanus!brand)