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From: f89ba@rigel.efd.lth.se
Newsgroups: comp.sys.ibm.pc.misc
Subject: Interrupt sharing
Message-ID: <1991Apr8.170234.24810@lth.se>
Date: 8 Apr 91 17:02:34 GMT
Sender: newsuser@lth.se (LTH network news server)
Reply-To: f89ba@rigel.efd.lth.se
Organization: Lund Institute of Technology,Lund, Sweden
Lines: 20

I'm planning on letting my modem (COM3) and the
LPT2 port share IRQ5. This should work since I don't use
the second parallel port but need an extra serial port.

However, is it possible to let two devices (in particular
a serial port and a parallel port) share an interrupt
line without the risk of damaging the computer's hardware?

Although not particularly well informed in this area, I could
imagine a scenario with one device raising the signal and
the other one lowering it, causing a "short circuit" between
+5 volts and 0 volts, or am I way off here?

In either case, I would appreciate some facts before I flip
the dipswitch!

Please email any responses since I cannot keep up with
comp.sys.ibm.pc.misc

  Bengt Ask, Lund Institute of Technology, Lund, Sweden