Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!apple!well!brent
From: brent@well.sf.ca.us (Brent Southard)
Newsgroups: comp.windows.ms.programmer
Subject: Re: windows & assembly level interrupt handlers
Keywords: midi, assembly, interrupts, help!
Message-ID: <23466@well.sf.ca.us>
Date: 6 Mar 91 03:52:03 GMT
References: <972@grapevine.EBay.Sun.COM>
Distribution: na
Organization: Whole Earth 'Lectronic Link, Sausalito, CA
Lines: 28

In article <972@grapevine.EBay.Sun.COM> g-man@EBay.Sun.COM (Luis Navarro) writes:
>I am trying to write a Windows 3.0 application that uses an assembly
>level interrupt handler to handle MIDI...
>
>I have obtained some C/assembly code originally written for interrupt
>driven MIDI communcations in DOS.  The assembly level stuff consists of
>the interrupt handler (an interrupt is generated for every MIDI byte that
>arrives at the MIDI interface) and the data i/o.  The C code uses the
>assembly routines to do the rest.  Now I am trying to use this assembly
>code in a relative simple windows program and am having some great 
>difficulties.

The interrupt handler must be in a FIXED code segment, and should be in a
DLL (dynamic link library).  In order for you to attach the handler to the
interrupt in protected mode you will need to use some DPMI (dos protected
mode interface) services.  You can get the DPMI spec free from Intel, or
download it from CompuServe.  Sorry, I don't have the number for Intel
handy, but someone on the net will...

Once your handler is installed, it should be a simple matter for it to
dispatch messages to any windows who care to listen.

brent
-- 
brent southard  (313) 643-1971   |   usenet:  ...!well!brent
ImageTech Corp  (313) 353-7900   |   bix:     brent

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