How early computers TRICKED TVs into making color (out of nothing at all)

Video Description

A deep-dive into composite color artifacts on NTSC. How did early computers sometimes generate color without an actual color signal? The Apple 2 line is considered the pioneer of this technique, where ALL of its colors were generated using this odd glitch of the NTSC standard. But color artifacts were exploited even earlier. Today we explore NTSC signals, color generation (both the proper way, and this odd "artifact" way), how artifacting was exposed by the hardware to early software developers, and the history of how early computers adopted this technique, including Home Pong, the Atari 8-bit computers, the entire Apple 2 line (other than the gs), the IBM PC CGA graphics card, and the TRS-80 Color Computer. Also, what's up with the color swapping that happens on the CoCo 1 and 2 when you hit the restart button? More CoCo Town Fundamentals: https://www.youtube.com/watch?v=756L40drupY&list=PL04L4HEkCiu8A28SVtv7gPj-nlrRkRDP_ Writing a retro game in assembly: https://www.youtube.com/watch?v=OLKpE-wkw0w&list=PL04L4HEkCiu-iBx4exoVfE8C50F-StqV6 More on the CoCo VDG: https://www.youtube.com/watch?v=EuVOrydl4xo&list=PL04L4HEkCiu8ky-EkaxEJ0ozmEjjVou5l Music: https://soundcloud.com/david_broman/soundtrack-for-vintage-hi-res-animation https://soundcloud.com/david_broman/dawn https://soundcloud.com/david_broman/remember-when https://soundcloud.com/david_broman/dream-in-8-bits "Friendly Dance" by Nico Staf "Icelandic Arpeggios" by DivKid Some music made with cocoretro sound library: https://www.pianobook.co.uk/packs/coco-retro/ Sources and additional information: Woz's US Patent #4136359 CoCo 1/2 MC6847 VDG Data Sheet: https://colorcomputerarchive.com/repo/Documents/Datasheets/MC6847T1%20MOS%20Video%20Display%20Generator%20%28Motorola%29.pdf mc1372 RF Modulator data sheet: https://www.cs.cornell.edu/~kt/post/6502-4/MC1372-tv.pdf CoCo 2 service manual: https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/Color%20Computer%202%20NTSC%20Service%20Manual%20%2826-3134%20%26%2026-3136%29%20%28Tandy%29.pdf CoCo 3 service manual: https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/Color%20Computer%203%20Service%20Manual%20%28Tandy%29.pdf Tepolt on CoCo 3: https://colorcomputerarchive.com/repo/Documents/Books/Assembly%20Language%20Programming%20for%20the%20CoCo3%20%281987%29%20%28Laurence%20A%20Tepolt%29.pdf https://www.ntsc-tv.com https://en.wikipedia.org/wiki/Composite_artifact_colors https://en.wikipedia.org/wiki/NTSC https://en.wikipedia.org/wiki/Color_killer https://en.wikipedia.org/wiki/Allan_Alcorn https://www.sigidwiki.com/wiki/NTSC_Broadcast https://www.extron.com/article/ntscdb1 https://www.extron.com/article/ntscdb2b https://www.extron.com/article/ntscdb3 https://www.extron.com/article/ntscdb4 https://paleotronic.com/2018/10/03/apple-ii-colour-computer-graphics/ https://history-computer.com/wp-content/uploads/2021/01/Apple_II_IMG_4227-2048x1366.jpg https://spectrum.ieee.org/al-alcorn-creator-of-pong-explains-how-early-home-computers-owe-their-color-to-this-one-cheap-sleazy-trick https://spectrum.ieee.org/build-this-8bit-home-computer-with-just-5-chips https://nerdlypleasures.blogspot.com/2013/09/the-overlooked-artifact-color.html: https://nerdlypleasures.blogspot.com/2013/11/ibm-pc-color-composite-graphics.html https://nerdlypleasures.blogspot.com/2021/10/apple-ii-composite-artifact-color-ntsc.html https://sagargv.blogspot.com/2011/04/ntsc-demystified-part-2-color-encoding.html https://codeandlife.com/2012/10/09/composite-video-decoding-theory-and-practice/ https://www.6809.org.uk/xroar/doc/xroar.shtml https://github.com/AppleWin/AppleWin NTSC 8-bit Color on the Color Computer 3 (john linville): https://www.youtube.com/watch?v=gc6Eu7IansE NTSC Artifact Colors - The Next Generation — David Schmenk — KansasFest 2017: https://www.youtube.com/watch?v=S8ZsefIEnvE Sprite Compiling for Apple Hi Res – Quinn Dunki – KansasFest 2017: https://www.youtube.com/watch?v=byVvMsW__Cc https://www.youtube.com/@NerdlyPleasures https://www.youtube.com/@HowTechTo https://www.youtube.com/@crysknife007 https://www.youtube.com/@moving-to-another-account A "different Woz"'s US Patent #20240341412 00:00 Intro 01:54 The software developer perspective 04:59 TV picture signals 10:43 Color artifacts 13:48 A brief history of computer artifact colors 17:33 The reset conundrum 21:21 Just for fun