[Coco] [Color Computer] The evolution of the Coco..

[James Diffendaffer]

I found the HOT CoCo article with the lowercase mod.

I got to thinking about it and by adding a larger ROM and a paging
circuit + a register to select different character set pages you could
scroll the characters just by writing a single byte.

It does require creating lots of character tables and a screen to go
with them. 

This would even let you make the demo in Basic!  The scroll takes
place with a single poke!  Sure it's cheating but it would work!


--- In ColorComputer at yahoogroups.com, "James Diffendaffer"
<jdiffendaffer at y...> wrote:
> 
> The CoCo 1/2's VDG does support the use of an external ROM for it's
> character set.  Look up one of the old lower case mods and change the
> character set to have the additional characters and you can sorta do
> it.  You couldn't do the characters with a different brightness that
> way but it's the only fast way I know of to do it.  That would also
> exclude the use of a CoCo 3.
> 
> Doing it with graphics would be slow.  Moving that much on screen at a
> time requires more MHz than the CoCo can muster and some hardware
> accelleration wouldn't hurt either.  Page flipping could work but you
> couldn't fit enough pages in RAM without duplication of the characters
> and changing the video address to scroll through a giant page of
> graphics would probably jump too much... but I never really spent time
> programming the CoCo 3.
> 
> I don't see why someone shouldn't do it.  So what if it's slow.  If a
> faster CoCo becomes available in the future if could run fast enough.
> 
> 
> 
> --- In ColorComputer at yahoogroups.com, "Glen VanDenBiggelaar"
> <glenvdb at h...> wrote:
> > I am not sure if can be done exactly the same. I have attached the
> poster, 
> > and some charaters are bigger (in the foreground) and some are
> smaller. also 
> > it looks like japanese characters and backwards characters. but I do
> think 
> > it can be close, its just the random "speeds" of the different
> collums that 
> > might not be able to re produce. (sorry in advance for the big file
> all you 
> > dial up users)
> > >
> > -Glen
> > >Right, I'm gonna try now!
> > >
> > >
> > 
> > >
> > >
> > >
> > >





Brought to you by the 6809, the 6803 and their cousins! 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/ColorComputer/

<*> To unsubscribe from this group, send an email to:
    ColorComputer-unsubscribe at yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/