🚀 go-pugleaf

In article <1993Jan7.122713.17450@walter.cray.com> kelly@spyro.cray.com (Matt Kelly) writes:
>I built a home-brew MIDI interface for my synthesizer setup.  When
>I built it, I had an old PC-XT clone.  I hooked up the receiver
>section of the interface's UART chip (8250) to IRQ2.  This worked
>just dandy.
>
>Now I have a 386-SX system.  IRQ 2 doesn't work anymore.  All docu-
>mentation I have read has said that IRQ2 is a "cascade" interrupt.
>WHAT DOES THIS MEAN, AND HOW DO I MAKE IT WORK????

The PC and XT had one IRQ controller chip, driving the interrupt pin on the
CPU. The AT uses a second IRQ controller, fed through IRQ2 of the first
chip, to signal the CPU. IRQ5 (formerly the HDD controllers IRQ) is now
used by LPT2 (normally!)

>
>In an effort to speed up my success, I rewired the interface so
>that it would use IRQ5 instead of IRQ2.  Still no interrupt response.
>
>I took the software I was using on the old system (which I wrote),
>and re-compiled the .ASM files which handle the interrupts so that
>they would use IRQ5 instead.  Total death.
>
>Any help would be appreciated.  The system I have is a Goldstar with
>2 serial, 1 parallel, 1 game port, 40 meg HD, 2 floppy drives, VGA.

What IRQ is the game-port on?


--
--- Kiz (aka Ian Stuart) istuart@nyx.cs.du.edu
	{ Chivalry is not dead! - Just the Horse }