4 ms·

Spoilers: The trick was pretty easy to guess but still a lot of fun to see put into practice. The EGA monitor bits, and more broadly just the idea of trading c

Spoilers: The trick was pretty easy to guess but still a lot of fun to see put into practice. The EGA monitor bits, and more broadly just the idea of trading color bit depth to multiplex signals for multiple monitors into a single framebuffer and physical output is pretty cool. The Windows display driver idea actually implemented on real hardware would be tons of fun. I could have seen products actually doing this "back in the day" to do multi-head setups. I'm kinda surprised examples don't exist.

badc0ffee 4mo ago
I think it's just that monitors were so much more expensive then, especially those capable of the 350-line EGA mode.
- EvanAnderson 4mo ago
  I'm sure that was a factor. As much as certain job roles today love multi-head (I'm particularly thinking head spreadsheet users) I could still have seen it being a possibility. Certainly, multi-head for AutoCAD was "a thing" pretty early, albeit the paradigm there was one monitor for graphics and another for text.
  - genxy 4mo ago
    Multihead for debugging full screen apps is/was pretty sweet. Now we just use ssh or a remote debugger. I haven't finished the video, fingers crossed that he hooked 4 joysticks for multiplayer pong. Didn't realize how wholesome 8bit guy is, great channel.
    - utopcell 4mo ago
      Id soft folks were using 2 graphics cards, an EGA/VGA and an MDA one to do multihead debugging. It was possible because the two card technologies actually mapped their frame buffers onto two separate address ranges. Cool stuff.
  - FarmerPotato 4mo ago
    This was the way of the first TMS34010 cards for Autocad (circa 1988). You'd have a EGA/VGA card for the host, and the graphics processor would drive the high-resolution graphics display. There were 50+ vendors with a 340 solution for the high-end, before SVGA. Later, vendors conceded to adding a VGA port integrated alongside. In Karl Guttag's recent talk on the 34010 (VCFSW YouTube channel) he mentions being contacted by Bloomberg for their multi-up terminal. When it shipped in the early 90s, it was the first dual display system I'd seen. Wall Street later began buying 4-display Matrox cards.
- deleted 4mo ago
  [deleted]
- MBCook 4mo ago
  Given you would have to do all the display stuff through bit math on the framebuffer I imagine interactive use would be horribly slow. You could certainly use it to display other pages of a spreadsheet or something but I don’t think I’d want to type into a word processor that was doing it.
  - rep_lodsb 4mo ago
    16-color EGA and VGA had separate bitplanes, so writing 4 monochrome images would take the same time as a single one in color.
    - MBCook 4mo ago
      Oh I forgot about the concept of bitplanes. Yeah that would make it easy.
- walrus01 4mo ago
  As I recall, some years later than this (referencing EGA monitors from the 80s), a 14 inch 1024x768 capable 75 Hz capable SVGA monitor with a reasonable dot pitch of 0.28, nothing special, something you might find bundled with a 386DX/40 or similar from a clone builder was something like $400 in 1992. This would be the inflation adjusted equivalent of $970 today. So basically like buying a really nice super high refresh rate 32" gaming display.
  - badc0ffee 4mo ago
    Apparently the original IBM 5154 EGA monitor was $850 in 1984 dollars, or like $2800 today. Of course there were cheaper compatible monitors available shortly after that. The first monitor I bought myself was a 17" SVGA monitor, in 1997. I think I paid $700 Canadian, but I would have paid a premium for a nice picture (I think it was a Viewsonic?).
jchw 4mo ago
Since everyone is vibe coding everything anyway I fully expect there to be a Windows 3.x display driver that works this way soon. I'm sure people in the retro computing hobby feel a certain way about this, but it's definitely also hard to deny the amount of "Project Structure" in README and "// ---- Input Handling ---------------------------------------------" snippets I've been seeing lately in a lot of new homebrew and other projects. (Another fun one: comments that are justified to a specific column but off by one in only one of them. I'm sure humans do this too, but AI does it more.) I don't really care that much personally although it's silly that people kind of have to be wink-wink-nudge-nudge about it for the foreseeable future.
- TacticalCoder 4mo ago
  Yes what's with that in LLM output? It used to be a big thing in the nineties: I've got old .asm source code of mine where I used to do that. But somehow LLMs love to insert dashes everywhere: dashes in source code an em-dashes in prose. Just why? Did they parse lots of early code and thought it was cool to insert, in modern programming languages, comment lines full of dashes? > Another fun one: comments that are justified to a specific column but off by one in only one of them. Oh yes, all the time. And besides the fact that there are the off-by-ones errors, it of course looks horrible in Claude Code CLI seen that what you see is not what the LLM did output (because they vibe-coded their "real time game engine" that changes characters, for no reason, on the fly). It's 2026 and we've got "intelligent" machines doing this: // ------------------------- // ------------------------ // ----- Input Handling ---- // ------------------------ // |--------------+-------+------| // | Potentiometer | Min | Max | // |--------------+-------+------| Which they'll probably "fix" by adding the following vibe-coded tool, of course hidden in their pipeline: ascii_table_to_unicode_mismatch_alignment_fixer(...); What an era.
  - trollbridge 4mo ago
    Yes, they’re trained in lots of old code.
  - sixothree 4mo ago
utopcell 4mo ago
"Every mathematician wants to discover a mathematician's lemma." It might have been easy to guess, but you didn't really think of it in the past 51 years since the Commodore 128 was introduced, did you?
- myrandomcomment 4mo ago
  The C128 was introduced in January 1985 at the CES in Las Vegas, so 41 year. Read your post and thought, "I am not that old!" I went from a VIC20 to C64 then to a C128D in 1987. Then moved a 486DX50 running OS/2 in 1990.
  - deleted 4mo ago
    [deleted]
HerbManic 4mo ago
Would be the kind of product you see demoed on The Computer chronicles from Eagle New Global Tech corporation, you gander at it thinking "Wow, one day I will get that" and then you never hear from the company again as they only sold 4,000 units. So like most of the gadgets from the 90s.
twh270 4mo ago
Back in the VGA days, I worked for a video card maker, and one of them supported a multi-head configuration. You could stick as many as 16 into one machine, if it had enough slots. Thus driving 16 monitors at once. I was responsible for taking the stock Windows 3.1 display driver for the chipset and modifying it for multi-head support. That was a really fun and challenging project, and ultimately very satisfying. I am pretty sure there were a few customers who needed the full 16-card setup. BTW this was done in the day when drawing pixels on a screen was all done via the CPU telling the card "draw /this/ pixel with /this/ color". Good times!

badc0ffee 4mo ago

I think it's just that monitors were so much more expensive then, especially those capable of the 350-line EGA mode.

EvanAnderson 4mo ago
I'm sure that was a factor. As much as certain job roles today love multi-head (I'm particularly thinking head spreadsheet users) I could still have seen it being a possibility. Certainly, multi-head for AutoCAD was "a thing" pretty early, albeit the paradigm there was one monitor for graphics and another for text.
- genxy 4mo ago
  Multihead for debugging full screen apps is/was pretty sweet. Now we just use ssh or a remote debugger. I haven't finished the video, fingers crossed that he hooked 4 joysticks for multiplayer pong. Didn't realize how wholesome 8bit guy is, great channel.
  - utopcell 4mo ago
    Id soft folks were using 2 graphics cards, an EGA/VGA and an MDA one to do multihead debugging. It was possible because the two card technologies actually mapped their frame buffers onto two separate address ranges. Cool stuff.
- FarmerPotato 4mo ago
  This was the way of the first TMS34010 cards for Autocad (circa 1988). You'd have a EGA/VGA card for the host, and the graphics processor would drive the high-resolution graphics display. There were 50+ vendors with a 340 solution for the high-end, before SVGA. Later, vendors conceded to adding a VGA port integrated alongside. In Karl Guttag's recent talk on the 34010 (VCFSW YouTube channel) he mentions being contacted by Bloomberg for their multi-up terminal. When it shipped in the early 90s, it was the first dual display system I'd seen. Wall Street later began buying 4-display Matrox cards.
deleted 4mo ago
[deleted]
MBCook 4mo ago
Given you would have to do all the display stuff through bit math on the framebuffer I imagine interactive use would be horribly slow. You could certainly use it to display other pages of a spreadsheet or something but I don’t think I’d want to type into a word processor that was doing it.
- rep_lodsb 4mo ago
  16-color EGA and VGA had separate bitplanes, so writing 4 monochrome images would take the same time as a single one in color.
  - MBCook 4mo ago
    Oh I forgot about the concept of bitplanes. Yeah that would make it easy.
walrus01 4mo ago
As I recall, some years later than this (referencing EGA monitors from the 80s), a 14 inch 1024x768 capable 75 Hz capable SVGA monitor with a reasonable dot pitch of 0.28, nothing special, something you might find bundled with a 386DX/40 or similar from a clone builder was something like $400 in 1992. This would be the inflation adjusted equivalent of $970 today. So basically like buying a really nice super high refresh rate 32" gaming display.
- badc0ffee 4mo ago
  Apparently the original IBM 5154 EGA monitor was $850 in 1984 dollars, or like $2800 today. Of course there were cheaper compatible monitors available shortly after that. The first monitor I bought myself was a 17" SVGA monitor, in 1997. I think I paid $700 Canadian, but I would have paid a premium for a nice picture (I think it was a Viewsonic?).

jchw 4mo ago

Since everyone is vibe coding everything anyway I fully expect there to be a Windows 3.x display driver that works this way soon. I'm sure people in the retro computing hobby feel a certain way about this, but it's definitely also hard to deny the amount of "Project Structure" in README and "// ---- Input Handling ---------------------------------------------" snippets I've been seeing lately in a lot of new homebrew and other projects. (Another fun one: comments that are justified to a specific column but off by one in only one of them. I'm sure humans do this too, but AI does it more.) I don't really care that much personally although it's silly that people kind of have to be wink-wink-nudge-nudge about it for the foreseeable future.

TacticalCoder 4mo ago
Yes what's with that in LLM output? It used to be a big thing in the nineties: I've got old .asm source code of mine where I used to do that. But somehow LLMs love to insert dashes everywhere: dashes in source code an em-dashes in prose. Just why? Did they parse lots of early code and thought it was cool to insert, in modern programming languages, comment lines full of dashes? > Another fun one: comments that are justified to a specific column but off by one in only one of them. Oh yes, all the time. And besides the fact that there are the off-by-ones errors, it of course looks horrible in Claude Code CLI seen that what you see is not what the LLM did output (because they vibe-coded their "real time game engine" that changes characters, for no reason, on the fly). It's 2026 and we've got "intelligent" machines doing this: // ------------------------- // ------------------------ // ----- Input Handling ---- // ------------------------ // |--------------+-------+------| // | Potentiometer | Min | Max | // |--------------+-------+------| Which they'll probably "fix" by adding the following vibe-coded tool, of course hidden in their pipeline: ascii_table_to_unicode_mismatch_alignment_fixer(...); What an era.
- trollbridge 4mo ago
  Yes, they’re trained in lots of old code.
- sixothree 4mo ago

utopcell 4mo ago

"Every mathematician wants to discover a mathematician's lemma." It might have been easy to guess, but you didn't really think of it in the past 51 years since the Commodore 128 was introduced, did you?

myrandomcomment 4mo ago
The C128 was introduced in January 1985 at the CES in Las Vegas, so 41 year. Read your post and thought, "I am not that old!" I went from a VIC20 to C64 then to a C128D in 1987. Then moved a 486DX50 running OS/2 in 1990.
- deleted 4mo ago
  [deleted]

HerbManic 4mo ago

Would be the kind of product you see demoed on The Computer chronicles from Eagle New Global Tech corporation, you gander at it thinking "Wow, one day I will get that" and then you never hear from the company again as they only sold 4,000 units. So like most of the gadgets from the 90s.

twh270 4mo ago

Back in the VGA days, I worked for a video card maker, and one of them supported a multi-head configuration. You could stick as many as 16 into one machine, if it had enough slots. Thus driving 16 monitors at once. I was responsible for taking the stock Windows 3.1 display driver for the chipset and modifying it for multi-head support. That was a really fun and challenging project, and ultimately very satisfying. I am pretty sure there were a few customers who needed the full 16-card setup. BTW this was done in the day when drawing pixels on a screen was all done via the CPU telling the card "draw /this/ pixel with /this/ color". Good times!