Accessing COM3 and COM4

Article View: comp.sys.ibm.pc.programmer

Article #763

Back to comp.sys.ibm.pc.programmer Previous Next

#763

From: Bryan So
Date: Sat, 16 Jun 1990 00:20

11 lines
710 bytes

Somebody must have posted this before, but I am relatively new to 
this newsgroup, so... can somebody show me the general method to
speak to COM3 and COM4?  Can I simply service IRQ3 & IRQ4 as if
they are COM1 and COM2?  If so, how can I distinguish whether the
interrupt is raised by COM1 or COM3 (take IRQ3 for example)?

Thanks in advance.


Bryan So

Technical Details

Message-ID: <10595@spool.cs.wisc.edu>

Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!cs.utexas.edu!uwm.edu!uwvax!brownie.cs.wisc.edu!so

Show Full Headers

Complete Article Headers

Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!cs.utexas.edu!uwm.edu!uwvax!brownie.cs.wisc.edu!so
From: so@brownie.cs.wisc.edu (Bryan So)
Newsgroups: comp.sys.ibm.pc.programmer
Subject: Accessing COM3 and COM4
Message-ID: <10595@spool.cs.wisc.edu>
Date: 16 Jun 90 00:20:00 GMT
Sender: news@spool.cs.wisc.edu
Organization: U of Wisconsin CS Dept
Lines: 11