Subject: Re: A7000+ install problems
To: Chris Gilbert <chris@buzzbee.freeserve.co.uk>
From: David Brownlee <abs@netbsd.org>
List: port-arm32
Date: 10/29/2000 23:40:20
On Fri, 27 Oct 2000, Chris Gilbert wrote:

> > > > 	Is the A7000 special with respect to needing the correct amount
> > > > 	of video RAM set in the bootloader? Does anyone know how to probe
> > > > 	that?
> > >
> > > I just guessed at the amount.  I just randomly chose 1024K.  Later on I
> > > also tried 2048K and that worked as well.  So, I don't think it matters
> > > that much.  I'm not using X yet, it might be more important for that.
> >
> > 	Wasn't there something special about the A7000 and Video RAM (such
> > 	as it didn't have any and just used some of the normal RAM?)
>
> Yes, you use the DRAM, as can a RPC with no VRAM.  The amount needed is the
> same as under Risc-OS, eg 1024x768 at 256 (1byte) colours is about 768KB.
>
	So the value is only needed on a machine without VRAM? On a
	machine with 1MB of VRAM can you set it to 2MB to use 2MB of DRAM
	with higher resolution/bpp?

> Perhaps if we calculated this on the fly and played with it better that would
> help?  Another option is to make the boot loader query for vram (if there's a
> way on the Risc-OS side) and say excuse me not vram or dram allocated...
>
	That sounds like the best plan.

> Perhaps it's time to start up that wish list of things to try to get into 1.6
> (and smaller stuff into 1.5.x)
>
	For 1.5 would it make sense to default the value to 768KB?

> I know that there's a list of PR's that need to be looked at.

	Definitely - can you submit one for this?


                David/absolute
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