Date   : Sat, 17 Aug 2002 09:33:22 +1200
From   : Michael Foot <mjfoot@...>
Subject: Re: Firetrack emulation again

In message <Pine.LNX.3.96.1020816151010.15315A-100000@...>
          jim <jim@...> wrote:

> On Fri, 16 Aug 2002 Richard_Talbot-Watkins@... wrote:
> > A0-A2.  It may be something like RA3/RA4 are connected to the
> > display enable pin, so that instead of the expected 'wraparound'
> > within character rows when the scanline count per character is
> > greater than 8, we simply get a blanked display.
> 
> This is in fact the case (well, RA3 anyway, RA4 isn't used). As far as the
> CRTC is concerned it's just got a 10-line character to display, but
> because of the way its address pins are connected up lines 0-7 read
> successive bytes of memory and 8-9 are blanked. 

Thanks for the summary. I thought there may be something hardwired like 
that. However, it does not help with my initial point 2 with regards to FireTrack
because it will still display blank lines when R9 goes from &7 to &F. Maybe
my timing is wrong or something?

Thanks,

Mike.

-- 
Michael Foot <mjfoot(at)paradise(dot)net(dot)nz> *
http://homepages.paradise.net.nz/mjfoot/
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