Saturday 15 September 2018

Time for an update ....

Well , it is. Partly because I have been away for a few days, mind.

Anyway, while I was away I decided to redesign the whole thing backwards to fit a more ColorForth style design. So what I have now is a 'kernel' Spectrum .SNA file, which contains the (simple) compiler and a bit of support stuff.

So the way it works now ; the boot code, which is written in a textified Color Forth, is converted to the 8 bit characters I use - 6 bit ASCII plus 2 colour bits, and stored in the screen space. The compiler then compiles it or executes it from there (at the same time outputting the source in ColorForth format).

This is very much like Chuck Moore's ColorForth source, in style ; except rather than use constants I've bodged a five minute assembler into it. The two pictures are roughly the same bit of code - I couldn't find a decent colouring editor.

While I was away I was having difficulty sleeping, so I read the Spectrum Next's technical documents to try to get some shut-eye. This worked quite well, but not before I noticed that in the Low-Resolution (128x96x256 colours) mode the Next uses memory from 6000-7FFF as well as the usual screen RAM area. So additionally I've made it a bit more flexible in that it can be build anywhere.

I plan to page the top 16k ala Spectrum 128 to extend memory, but the 16k between there has to host the dictionary and common code ; otherwise it will go mad with task switching.

I'm also back on Arch Linux, fortunately for my sanity.

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