Post AlqaNK9fysSmI6H4Do by fozztexx@mastodon.fozztexx.com
(DIR) More posts by fozztexx@mastodon.fozztexx.com
(DIR) Post #AlqZuWPXKpwLu5xVz6 by foone@digipres.club
2024-09-10T02:58:02Z
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I've got two small monochrome CRT modules. They've got an unlabeled connection but from comparing with some other connectors I'm pretty sure it's just:Voltage/ground/video/H sync/V syncSo my question is, what's the easiest way to drive this? Like, some way I can make a raspi or VGA video card drive these?
(DIR) Post #Alqa74khTr8vt1qOzA by foone@digipres.club
2024-09-10T03:00:03Z
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It's something like this:An open frame CRT module for use inside a portable computer.https://www.omnivisionusa.com/Industrial-LCD-CRT-Monitors/replacement-crt/crt-monitors/7-inch-chassis-.html
(DIR) Post #AlqaFm709cFKgHQK4u by zarky@bitbang.social
2024-09-10T03:01:01Z
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@foone Post some pictures i may be able to help.. If they're 15khz youll need an appropriate signal that you're not likely to get from anything VGA based. If its 31khz try to feed the green line into the video signal, and H/V into their respective lines. See if feeding a straight composite video signal into the video line works too
(DIR) Post #AlqaNK9fysSmI6H4Do by fozztexx@mastodon.fozztexx.com
2024-09-10T03:01:42Z
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@foone Easiest? Probably CGA output with composite video. Has H+V+video.
(DIR) Post #AlqaT8vedGkND9USzA by philpem@digipres.club
2024-09-10T03:01:32Z
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@foone It depends on the video mode it expects. A VGA card should probably be able to drive it, but if it wants composite video style timing (525 or 625 lines), you'll probably need a sync separator and a composite source.edit: I think there's a way to hook a Pi up to generate VGA using an R2R DAC, but it's been ages since I looked. It has a parallel output too, on the GPIOs, it's meant for LCDs. I have no idea how to set the mode timing though.
(DIR) Post #AlqahZ1EQYPKBKyXnU by zarky@bitbang.social
2024-09-10T03:03:17Z
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@foone if its that one, it should take just about anything you give it. use the green line from any vga source, maximum 1024x768, and feed it the H/V where apropriate, should just work. start with 640x480 60hz and work your way up.
(DIR) Post #Alqahb4qm4USZ8gSiO by zarky@bitbang.social
2024-09-10T03:04:57Z
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@foone Looks like it also takes standard composite video too.
(DIR) Post #AlqaoB1m1aSJnkNlZ2 by nickzoic@aus.social
2024-09-10T03:05:50Z
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@foone VGA has separate H and V sync at TTL and colour channels at 0.7V so you should be able to run it directly off that, one color channel per monitor!
(DIR) Post #AlqbXhiZKVTGDg6n3o by RueNahcMohr@infosec.exchange
2024-09-10T03:16:19Z
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@foone Are they from a compaq portable?
(DIR) Post #AlqbwolwEsJBL0exyi by foone@digipres.club
2024-09-10T03:20:35Z
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I don't have any specs for what resolutions/rates it needs, though. So something that can flexibly try a bunch of different options would be handy
(DIR) Post #Alqc6RfsyDC4b7Q3vc by RueNahcMohr@infosec.exchange
2024-09-10T03:22:32Z
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@foone if you post a photo maybe one of us knows it...
(DIR) Post #AlqjdaEKsfSqMsHWYi by hattifattener@wandering.shop
2024-09-10T04:46:50Z
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@foone I'd think you could drive it off the GPIOs of a RP2040. I have no idea if a rπ by itself could meet the timing requirements, but if it can't, the glitches might be interesting(Or you could go the boring route and use purpose-built video hardware I GUESS)
(DIR) Post #AlqwaqkuHYzk9iXkZs by falken@qoto.org
2024-09-10T07:11:58Z
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@foone maybe https://github.com/tdaede/td-crt ? No personal experience but Brad and Will loved it in "Brad & Will Made a Tech Pod" ep. 248https://antennapod.org/deeplink/subscribe/?url=https%3A%2F%2Ffeeds.simplecast.com%2FqKIEAGzn&title=Brad+%26+Will+Made+a+Tech+Pod
(DIR) Post #AlsXBfFtnFO8i9qyRM by foone@digipres.club
2024-09-11T01:35:51Z
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okay I found a manual for a protocol analyzer that uses the same model of CRT, which has some technical details:So it's 16.66 KHz horizontal refresh, ~60hz vertical, and it uses a 5V signal for the video.