[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!

> > >

> > >

> > 

> > >

> > >

> > >

> > >






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