🚀 go-pugleaf

> In your examples, 11h means no ICW4, cascaded mode, edge triggered
> mode (The call address interval and interrupt vector address are
> ignored in iAPx-88/86 mode). 12h means no ICW4 and single mode, edge
> triggered.  13h means ICW4 needed, single mode and edge triggered.
> 
> to complete the picture, ICW2 is used to help generate vectoring
> addresses (on MCS-80/85 systems) and vector bytes (on iAPX-88/86).

OK, Brian, thanks for the response.  Now, off the top of my head, here is the
code.  Bear in mind taht this is from some communication routines that I have.
This is one section of the code (from what I can remember off the top of my
head).  I'd ask the original programmer, but there is no address.

		mov	al,11h
		out	20h,al

		mov	al,8
		out	21h,al

		mov	al,4
		out	21h,al

		mov	al,3
		out	21h,al

		mov	al,20h
		out	20h,al

Note that this code was in the interrupt set code, after the cli, but before
the sti (which was just after the final line above).

What exactly does this do?  The interrupt won't run without it (although it
should).  The actual interrupt also doesn't use a mov al,20h; out 20h,al at the
end of the interrupt.

I(deas?

Joshua Jensen