8-bit homebrew computers, analog electronics and 74-series madness!⚡️🪛
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2026-09-19T19:13:22Z Event JSON
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Last Notes npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ High praise indeed! npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ I've been experimenting with interlacing on my new 8-bit video card and it's finally working!!! npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ Fuck the first machine to pass the turing test. I wanna be the first human to fail it! npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ Well it never became a hit either. They sold less than 200. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ April 11th, 1976 - The #Apple 1 is released🍎 npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ Anyone else ever notice that DIP-40 chips are never boring? npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ yep OG VGA textmode is 720 by 400...pretty cursed in my opinion. 9 horizontal bits per character🤮 npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ Three generations of keyboard interface cards for my Z80 machine. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ decimal machines were pretty common in early computing. People weren't used to binary yet so lots of machines used BCD for arithmetic because it was easier for humans to understand and debug. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ In 1981 #IBM got the legendary Paul Rand to redesign their logo. He did not disappoint. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ it's just 640 with double wide pixels npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ By designing the icons for the 1984 #macintosh, Susan Kare added a much needed personal touch to the computer industry. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ oh I see. I just explained it badly. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ when the first edge falls, the other with still be high and you're just looking at that to tell the direction. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ thanks, I'll be writing drivers for it soon so this'll be useful. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ all the inputs are active low, so I'm just ANDing them all together and the negative edge generates an interrupt. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ https://en.m.wikipedia.org/wiki/Rotary_encoder npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ and yeah the backup battery is a 9V. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ no ADCs. They're rotary encoders so their output is digital. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ thanks. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ My #Z80 machine is getting some new input devices. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ I've been meaning to get this done for a few years. So happy I finally found the time to do it! npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ I'll take some of the MC34063s if they're still going? npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ i actually use a trick like this for my buffers. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ yeah Set and Reset aren't synchronous. The output will change the moment you pull those inputs low, they don't use the clock. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ wow, nice to see someone who used it back in the day. And yeah it's sad to see the Z80 go, especially since it's what got me into electronics. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ LittleFuse (Zilog's parent company) took the last orders for the #Z80 yesterday. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ if they pull 500mA then they're going to be running at 108°C. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ you'll need LARGE heatsinks for those voltage regulators. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ yeah it's also the most undemocratic system you can imagine. Very prone to corruption, sensorship, misinformation. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ we gave up on this method in the late 90s because there was just too much information. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ good luck trying to index the whole internet npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ i'm guessing you have to ignore the M1 chip for this to be true. npub1g8rkdfne0p6ktkkylyr25fzdpm7sctn86aydsl29h0lcc9gd6desakwa56 Electrotopia⚡️ Finally got my 320 by 200 #VGA video card PCBs last week. Glad to be off the breadboard!
