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A project log for Sol-20 Reproduction

I am making a full sized Sol-20 reproduction, the first fully assembled microcomputer with a built-in keyboard and television output.

Michael GardiMichael Gardi 09/27/2021 at 21:520 Comments

When I was working on the virtual display I skipped a couple of improvements in the interest of finishing some of the other stuff like keyboard and virtual cassette tapes. The first was the aspect ratio which was more like 16:9 than the period 4:3. This has been adjusted by altering the character ROM images, basically by doubling every scan line. 

I have also added an optional virtual blinking cursor, the original's display hardware took care of this. The original Sol-20 also had a bank of 8 dip switches that controlled display options like SOLID and BLINK cursor. I'll be adding a similar set of switches to my reproduction, but for now the BLINKING_CURSOR option is a Boolean in my Python code.

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