[Coco] Access to 225 lines in BASIC

Nick Marentes nickma2 at optusnet.com.au
Mon Oct 20 14:07:06 EDT 2014


On 20/10/2014 10:48 PM, Bill Pierce via Coco wrote:
> Nick, I think (IMHO), that they kept the 192 due to the 8x8 font matrix for text characters. To go to the full resolution left extra "unused" lines, even if they went to an 8x7 or 7x7 (6x7?) font. They ran into the same problem when rewriting the screen drivers for NitrOS9. NitrOS9 allows you to setup the screen for the extra lines but it's always a little "off". It also made the math easier :-)
>   
>
> Bill Pierce
> "Today is a good day... I woke up" - Ritchie Havens
>   
>

I don't think that's it.

An 8x8 font matrix creates a perfect 40x25 text screen as well. It's 
just an extra line but one of thos POKE's even sets the maximium number 
of lines I had it doing 26 lines when I was experimenting with the 
320x225 mode.

The reason that Robert Gault gives in a previous message degarding the 
MMU blocks is correct and is what is causing the complication in using 
the highest res.

Nick


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