[Coco] Anyone try an 80x28 text screen on a CoCo3?

Robert Gault robert.gault at att.net
Mon Apr 23 02:32:11 EDT 2018

Many of you know that the GIME can be set for a max 225 lines on a screen; the default being 192.

I've just found a method for patching the ROM so that a WIDTH80 screen now displays 28 lines of text 
rather than the default 24; 192/8=24.
Let this be a challenge for you programmers. :) You also need to realize that 225/8=28.125 which 
will give you an extra horizontal scan line. That needs to be cleared with a CLS from the bottom of 
the screen.

I'll see if there is any interest in this and post the answer after you have a chance to try and 
solve the challenge.
I wonder why Tandy decided to use 24 rather than 28 lines of text.


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