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Date:	Wed, 2 Jan 2002 01:14:38 PST7
From:	"Steven Levine" <steve53@earthlink.net >
Reply-To:	scoug-help@scoug.com
To:	scoug-help@scoug.com
Subject:	SCOUG-Help: SBLive setup

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In <3C32B0DD.2DE6@peterskye.com>, on 01/01/02
at 11:06 PM, Peter Skye said:

>The drivers are chained. Typically the first driver asks its hardware if
>it needs service; if the hardware does want service then the driver
>INs/OUTs the necessary ports. The driver can then either pass the
>interrupt down the chain to any other driver which might want it, or
>return without passing the interrupt. If the driver doesn't attempt to

In general, this is a reasonable explanation of how it works in DOS. The
OS/2 device driver implementation is quite different and most of your
statements don't apply.

>while but as I recall there's a bit in the driver header which the driver
>programmer can set to choose either type of behavior.

>*Therefore*, you can either disassemble the drivers to see how the
>headers are set up *or* you can play with the sequence of the drivers
>until you find a sequence that works. :)

You're thinking of the shared access bit. This has nothing to do with IRQ
sharing. IRQ sharing is determined when the IRQ is allocated via a DevHlp
call.

Steven

--
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"Steven Levine" MR2/ICE 2.30a #10183 Warp4/FP15
www.scoug.com irc.webbnet.org #scoug (Wed 7pm PST)
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