Pseudonymous classic computing fanatic “c0pperdragon” has designed a board which extracts the highest-quality video attainable out of your basic Sinclair ZX Spectrum microcomputer — pushing out a “semi-digital” Lumacode sign for pixel-perfect upscaling on fashionable high-resolution shows.
“The ULAdigitizer is a small add-on board that may be put in right into a ZX Spectrum microcomputer to provide a Lumacode sign,” c0pperdragon explains of the compact gadget. “This sign comprises all the knowledge of the video display screen in a semi-digital kind that may be losslessly processed. At the side of an RGBtoHDMI upscaler or another suitable gadget, this may create a pixel-perfect show.”
The ULAdigitizer goals to ship crisp “semi-digital” video from unique ZX Spectrum {hardware}, with somewhat intelligent visitors sniffing. (📷: c0pperdragon)
Launched in 1982 because the successor to the Sinclair ZX81, which was recognized within the US because the Timex Sinclair 1000, Sinclair Analysis’s ZX Spectrum was an reasonably priced, 15-color, eight-bit dwelling pc with iconic rubber keyboard — recognized, roughly affectionately, because the “lifeless flesh” keyboard for its considerably disagreeable finger-feel. As customary, the gadget outputs its video over an analog RF connection — not solely requiring a TV with analog tuner to decode but additionally introducing no small quantity of noise into the combination.
“The unique video output of dwelling computer systems of the Eighties is of fairly low high quality,” c0pperdragon explains. “Utilizing a contemporary TV to show this sign usually doesn’t make this any higher. The truth is it usually simply exaggerates the seen noise. Additionally there’s principally no method to enhance the analog sign due to the random nature of the noise.”
The board comes with an RCA output, which may be linked to upscalers able to decoding a Lumacode sign. (📷: c0pperdragon)
The ULAdigitizer goals to repair that. Seated on the board beneath the Ferranti Uncommitted Logic Array (ULA), the board makes use of a field-programmable gate array (FPGA) to smell the ULA alerts and regenerate the video information on the fly in c0pperdragon’s “semi-digital” Lumacode format. When linked to an appropriate decoding gadget, similar to an upscaler, this turns into a pixel-perfect rendition of the image — no noise, no blurring, simply precisely what you have to be seeing however was by no means achievable again within the Eighties.
Particulars on the ULAdigitizer and the Lumacode format can be found on c0pperdragon’s GitHub repository; assembled boards can be found on Tindie at $34 every, prepared for set up right into a ZX Spectrum. The maker has additionally designed equivalents for different microcomputers, together with the Commodore VIC-20, Commodore 64, and Commodore 128, and the Atari 2600/VCS video games console.
