+retrogamer33 on PC beeper only square waveform is supported, and only control for output is setting the frequency, and of course you can silence it (if you don't it plays at that frequency until some other program changes frequency, or until powering down - I'm assuming spectrum had a bit more of ways to control it?
I was not certain about your knowledge of limitations of PC speaker, so I wrote that tiny explanation just in case, as I was really interested to ask about the assumed differences between it spectrum 48k's sound generation. Like was the speaker just directly accessed and thus software controlled, or was there, as I would guess, a sound chip that controlled the speaker, and software must access and controls the sound chip - exactly like with C-64, but different features, limitations and capabilities? If there's link(s) to information of this, I'd love to read... Is there different waveforms? Can you set attack, sustain & decay to do different "instrument sounds", or use filters like hi/lo-cut, etc. and all that information of how was the nice sounds of it's single tone speaker (sorry if that was incorrect, can't recheck while commenting on phone) made? If you do reply with any kind of information, I'll be very thankful :)
Let me chip in here. While the PC's timer chip could be programmed to output a square wave to the speaker, the Speccy's speaker could only be controlled by the CPU directly. Producing a square wave took most of the CPU power. And to produce different frequencies, you had to count CPU cycles to flip the bit at the right time.
@Brad Sanchez I see what you mean, but back then they didn't have cross compilers running on machines 30 years from the future. ;) And they didn't have google, stack overflow, nor github. Imagine trying to do this if you have to go to the library just to get a book about the 8088 instruction set. ;)
Computing technology grew so fast that software had to get tugged along with it, not promoting things like optimization and learning to fully utilize what was available. Makes me wonder how much we missed out on because some things just didn't get experimented with and optimized to its full potential, or even near it, before we were onto a new chip or hardware standard. What is even more interesting to consider, where would we be now if we could have had those software advancements with earlier hardware. I love that there is a community out there still programing on these classic platforms. Great demo.
For getting a slight impression, on what we are missing, because of the lack of optimization I recommend you watch or try yourself '.kkrieger' from '.theprodukkt'. (Both written correctly!) While it doesn't look too impressive nowadays, it was back then in 2002, because it's an ego shooter using just 64KByte.
Yeah optimization is heavily missed. That's why I mostly play old games (although some make CPU usage max out one of the cores for no reason) I was taking a look at Rocket League, an interesting new game multiplayer only and a few maps. It asks for 7GB of disk space. Why why why
@@FeelingShred Disk space? Mostly b/c of textures and those ain't able to "optimize"-away. But I fully agree on the general mindset of optimized code in general. I wouldn't even want to know how many ressources win10 is throwing out of the window just for getting stamped OK if it is halfway stable merged bunch of code... not mention some gaming engines (cry engine e.g.) which is more like turning your pc into a heater than gettin it to an efficient realtime rendering......
This is truly masterful, I don't know what to be more impressed by, the multicolour CGA graphics or the digital sound coming out the PC beeper at the end. It's all amazing. I remember hearing a 4 channel mod file played for the first time out the speaker of my 386PC and even then I was totally blown away.
Well in theory it was always posssible. Just shift the wave file 2 bits right, ad all 4 files together, snip it to 8 bit then just post it to the PC speaker buffert (if i remember corectly the beeper buffert is 10 byte long. And if you do it in say 8Hz that is pretty typical, you have to post it 800 times a second... that is doable.. but.. well your code have to be very quick to interupt.
@@matsv201 There is no PC speaker buffer. The PC speaker could only be toggled from in to out through a single bit on IO port 61h. To play digitized sound you had to use a PWM technique and do very high frequency writes to the port and treat the PC speaker as a 1-bit DAC. There was no hardware to assist you, so you had to do these writes directly in your code, timed through interrupts or counting clock cycles.
I thought this was awesome, got to the end and thought 'they cheated and were playing that MOD through a soundcard!' Then I realized they were pumping that through the PC speaker. That's some serious black magic, and makes the whole thing even more awesome!
oh, I remember noticing somewhere around 1995 a PC version of some tracker (can't remember the name, maybe impulse tracker 2), had among the usual ones at time, sound blaster 16, gravis ultrasound, etc., also support for passing through PC beeper - it sounds awful when compared to actual PCM, but amazing for something coming out of just PC speaker :)
+Jim Leonard Indeed, I should've chosen my words more carefully as I didn't mean to say this wasn't anything new nor special because I saw a tracker on Pentium 75MHz do it :) My point was the black magic wasn't playing MOD through PC beeper in itself, but doing it on 8088, and not only that, but doing it while also simultaneously doing all this very hardware intense (and impossible by technical specs ;D) stuff, and as if that magic's not black enough, it's (the music) played in sync with that "other stuff". So I really meant to point the attention of readers to what's really amazing about the player, just forgot to write anything, except that it wasn't that playing PCM audio through beeper was something new, without including what it is that made doing it here very special :) Sorry bout that.
@@robsku1 Fast Tracker II is the one you're thinking of. I just checked in DOSBox and v2.09 supports Ultrasound, Sound Blaster, Soundplayer, and PC Speaker in either single-bit or pulse mod modes. Of the speaker modes, pulse-mod sounds the best, but is on the quiet side, while the single-bit mode sounds terrible, but is a lot louder. Soundplayer is just an 8-bit LPT DAC, ala the Covox Speech Thing. Sounds almost as good as the sound cards, aside from a slight crackle that doesn't show up with the cards and gets worse when you move the mouse.
Came here after reading about it in Planet X3’s manual and DAMN! This is impressive... all of it. Having started my computing days with an 8088 and CGA, this looks like wizardry. Never knew this was possible... more please!
@@Parvex if you use the standard modus, yes you are right. But like this demo is full of tricks, the Atari has his own box of tricks (DLI for example). None the less, I don't care which was the better computer or so. I really enjoy to see what people nowaday can do with old hardware and doing things we never dreamed of back in the day :)
Hello! I came here to talk about the Demoscene Your team and other Demoscene groups did an awesome job! I'm a very young adult and your demos made me really love the Demoscene and the Retrogaming!! I really congrats you and everyone who contributed to the Demoscene. Your work is amazing and the music keeps in my head and will keep forever! I am amazed by the technical aspect of the demos and machines, I really would like to code some programs one day, even if I don't even know how to code a simple program for now. But I got a lot of decades to go ahead! Thank you again for your team and every Demoscene groups for your amazing work. I hope that you inspired a lot of people other than me! ❤
@@kaerucraft7100 I would start by browsing pouet.net and reading various BBS posts, although there is a lot of veterans there and a lot of it might not make sense. Also, older people tend to be "angry" and dismissive, so keep that in mind. Also find some pouet.net demos that have done very well and read the comments under them. If you're ready to join a discord, I believe discord.gg/XBgbQd22 is the most popular one, but make sure to introduce yourself as a beginner so that people can respond appropriately.
Awesome! Who would've thought such old hardware is capable of _this_ sort of craziness?! If only today's programmers could be as super-talented and competent as these guys; then we'd have much better optimisation, more competently-programmed games and fewer cheap console ports, for a start. Amazing work!
I wonder what would I need to connect the CGA to generic CRT monitor or TV (preferably, finding a CGA monitor would be too hard; I like collecting, but I'm barely an amateur, I rarely hunt for much, like with Macintosh SE/30 I got free from neighbour but was too late to save the keyboard from garbage dump, and I haven't even tried to find one), with antenna, SCART and... oh, composite, Of my old TV works. I have no idea, but what about flat screen tv, does that produce the same colour "errors"? And it has no composite, at least not separately, but one source it can use is "component", which has several similar connectors, and I've heard that it can support various similar systems that don't have all of the connectors, but even if that's true, I guess that has naught to do with composite? Then what about the old way of using tv's analog antenna connector, it was the default for c-64 and most 80's micro computers, and for Amiga 500 you could buy a device between it and tv to connect it via antenna connector, which was probably so used here because Finnish tv's didn't nearly always have composite, and SCART wasn't yet in everyone's tv's. So is there a converter from composite to tv antenna (PAL) that's cheap, and does it no bad to the colours? Other ways? Yes, the old TV has composite, but I'm unsure if it works.
You basically just need a bit of luck. Most TVs have composite in either via cinch connectors or scart (or both). Quite a few TVs are dual-standard, so they can take both NTSC or PAL composite signals. You probably have more luck with an LCD TV than with CRT, because it's easier to run an LCD at both 50 Hz and 60 Hz than it is for a CRT. For what it's worth, I used a Samsung LCD TV during development of this demo (it's a 'PAL' TV, I'm in a PAL country). NTSC artifacts work fine on it. On some TVs it will work, on others it won't. I have a newer Samsung LCD TV that only takes PAL composite. By the way, there was an optional antenna modulator module that can be plugged onto a CGA card, but I think they're extremely rare. And then you need an NTSC-compatible TV tuner, so you really do need an 'NTSC' TV, as most TVs only have a single TV tuner on board.
AIUI you'd need a complete IBM PC 5150. The timing is exact in this, so it only works on the actual PC. That's why I'm watching it on TH-cam and not DOSBOX or the like. @robsku, any composite monitor would be suitable for CGA's composite artefact-colour mode. All monitors used to be composite, way back when. The popular Commodore monitor, forget which one, supports it. Actually any TV over a certain age, too, supports composite through the "video" port, the single RCA connector. If IBM hadn't chosen a resolution of 320, an exact multiple of the NTSC colour clock, and used a cheap crap NTSC colour modulator, then that wouldn't be possible. And many of the old CGA games, which took advantage of artefacting, would have been stuck in utterly abominable cyan-on-bloody-magenta. Honestly no idea why IBM chose those two awful colours. Or why games programmers used that palette. It has black and white in it, but the other 2 colours are painful to see. The alternative was blue, green, red, yellow, much more soothing. Or even a third scheme with a bit of a combo.
@@Scalibq Most modern TVs will tune in the American VHF fine, as well as the UHF other countries use. They're all made in the same factories in China now, and it's cheaper to just put a universal tuner in, and control it with software. Finding an IBM CGA RF modulator will be almost impossible. But I can't think why a generic one wouldn't be fine. Give it 5V from the keyboard port or a disk drive power cable. That's if your TV doesn't support composite, which it probably does.
great experience watching this... true hardware exploration, refreshing muzak, and superb gfx to sort you out - Executed with attitude and style.. cheers!
Wow! Its fun to see renewed interest in NTSC artifact video modes on multiple platforms at roughly the same time (See Bill Buckel's BMP2DHGR on the Apple II) . That blurry composite video we all used to complain about was capable of doing something useful all these years!
*gobsmacked* This is easily one of the most interesting and well-put together demos I've seen in ages! Grats to the whole team on this impressive piece of code wizardry! =^.^=
unbelievable!!! I've no more words for such a mastery!!! please keep going, really looking forward to see those techniques applied to real programs/games, and difficult to hope for more but... who knows!!! BRAVI!!!!!
@@ryanpenrod1859 It most definitely is. It's just using a technique called PWM to produce much more complex sounds at the expense of eating up 99% of the cpu's cycles. It was also used by music trackers such as FastTracker 2. A few games on the ZX Spectrum did it too, although the speccy was more limited on memory
@@redpheonix1000 Cool, thanks for clarifying. That's what I meant I suppose, it is using direct CPU modulation instead of the usual timer-driven speaker inputs, aka square waves I guess.
CGA: 1024 colors VGA: 256 colors CGA Is officially better than VGA EDIT: I read about how it worked: CGA Composite/Artifacting:16 col CGA Text mode w/ Max scanlines=1:16 col CGA Pallete register:4 col 16 x 16 x 4 = 1024 col
@@ryanpenrod1859 It's using square waves, except instead of a timer chip controlling their length, it's done with software instead. The CPU can still only switch the speaker on or off. But with clever techniques and some physics, you can PWM several channels of "analogue" sound through it. Still only 1 and 0 though. Actually modern CD players (if they still make those) use the same technique in their DACs, at least the "1-bit" ones do. Just flipping one bit, very fast, several MHz for a 44.1KHz signal. The sound is better, and it doesn't rely on carefully set-up analogue circuits like an ordinary DAC. Delta-sigma is one method.
If an 8088 with CGA can do this, then my old crappy laptop with Intel Celeron N3050 laptop with Intel HD Graphics can run a demo with real life graphics, raytracing at 60FPS!!!
Classic computer effect's with picture art-machine also very change background scene and position image in demo is positive nice for culture eyes for view, for hear sound music. 🎞👏😇😯😑⌨
I don't normally comment on videos etc, but, holy shit.. Totally mind blown.. I wish I still had out old IBM so I could boot this baby up.. I may have to go an hunt one down just to try it... If I saw this back when I was a young'un... Jeez
Amazing. Great things are possible to the masters of disciplines, even seemingly limited ones . No one use the PS3 to its full potential, and no one used CGA graphics to their full potential until recently (in this demo). Having said that, despite how impressive the polyphony in the music from a monophonic one voice sound card was, the SID is a better sound card, and the same music would have sounded better in SID (plus, all of the tricks that you used here, I assume can be used on the SID, too). Anyway, 10 / 10, great job. faithInHumanity+=200; Edit: Wait, did that sound card play the music at the end, too? Holy bloody shit, is it really true? I don't know what to believe. Can some one who knows tell me the answer?
Yeah, the end credits are played on the PC speaker, with a really tight code, and I mean REALLY, basically using almost every single CPU cycle that isn't pushing the text onto the screen. Here is a writeup from the author: www.reenigne.org/blog/8088-pc-speaker-mod-player-how-its-done/ Basically a SID-like (due to the obvious limitations) .MOD player (albeit with some pre-processing to adhere to the bandwidth limits) using assembler sorcery in many clever ways to manage that on 8088 with only a puny PWM-controlled beeper :)
PCem (emulator) can *almost* run this 100% correctly. It has a 11% "metric cycle count" deviation, flickers like hell at 4:38 (screen resolution changes) and freezes at the beginning of the Credits scene. The timing also feels very slightly off.
@@JimLeonard Andrej Karpathy made a nice tutorial using the Python NN libraries for Python ("Let's build GPT: from scratch, in code, spelled out."). Reducing the training set to a minimum (children's books or simple number sequences) might do the trick.
This is the same series of cpu that power the raiden ar arcade machines though. Raiden uses an nec v30, which is a revision of v20 cpu, which is just a 8080+8088 in one. Also, the wonderswan uses a v20 cpu as well. The gameboy uses a customized and enhanced variant of the 8080 cpu which is labeled as sm83
Yes, but all of those systems have additional graphics and sound support chips. All of the graphics in this demo are created by the CPU manipulating individual bytes of video memory. No sprite hardware, no tiles, no redefinable character sets...
@@JimLeonard yeah, that is impressive, but this cpu is really powerful. The zx spectrum didnt have any support chips for graphics either and that has a weaker z80 cpu
I'm sure reading trixter.oldskool.org/2015/04/07/8088-mph-we-break-all-your-emulators/ and all of the pages it links to will take 3 hours; there's your documentary :)
What those guys did is great. I still think game programmers got lazy at late 90's and we still never saw the full potential of the Pentium 3 for example. If Quake could run in a Pentium 166MHz, I think much more could be milked from 600/700/800MHz CPUs. Even the Playstation does amazing stuff with only 33MHz
What makes the 5150 great is its expandability. Why not outfit one with a Professional Graphics Controller and a Music Feature card (or two, the documentation says a maximum of two is permitted in a system, although I'm not sure what that would do. I suggest first-party hardware because with the variety of stuff out there for the machine there's no other way to keep it in order.
So this is just awesome Jim. Really sweet stuff. Can't wait to read the write up. This is clearly what Andrew hinted at in a recent email exchange. I take it you are in text mode with the colurburst bit enabled and some type of 1/2 height character cell? What i love is the perfect match up of the composite artifact pattern to the target image. Converter has to be based on a calculated NTSC output - wow - fun optimization work. What was the oversampling rate of the NTSC simulator? (Or did yu guys get there another way?) Love the polyphonic at the end as well. Awesome - really great. The last thing I love about it is this: th-cam.com/video/9VPn5gkG_Qo/w-d-xo.html Yes Jim - it would make an awesome screen for a demo. :)
Lysergesaure1 It's now online and linked to from the technical blog post about the MOD player at www.reenigne.org/blog/8088-pc-speaker-mod-player-how-its-done/ .
2 man-years of work! If it had taken 2 years it would have been impressive! But between 6 of them, that's.... erm.... dammit this is when some device to calculate mathematically would be useful... 4 months! Does that include the original research? I suppose it does! Although the techniques, namely artefact colours, and pseudo-graphics 16-colour mode, were both long-known in the PC world, putting them together like this still deserves a shitload of credit, and especially for the effects achieved. Artifact colour had been used on PC games since the early ''80s, Ultima II is the example I can best recall. I didn't have a PC then of course, but I've always been an Ultima fan so bought the compilation years later. Any CGA game where the colours are in weird vertical stripes, often missing half of the stripes, is probably using artefact colouring. That is, there's no other reason to do graphics like that. You can look it up yourself, but basically it relies on the NTSC encoder on IBM's CGA card being a bit shit, cheap and shoddy. Although IBM choosing 320 pixels across, exactly half of the 640 pixels of NTSC (any multiple would have similar effects) also helped. Well, "helped". It was an unintended side-effect, pretty sure IBM never planned on anyone using it on purpose. It meant that in 320-pixel modes like CGA's 4-colour graphics modes, alternating pixels in stripes would show up on a composite monitor as extra colours, solid not striped. Basically the frequency of the signal, of lots of stripes, is a similar frequency, or related, to the colour-carrier frequency. This goes back to NTSC television back when they were inventing colour TV. In particular they wanted a system that would still produce a picture on old black and white sets, this being the 1950s. You couldn't start a channel broadcasting just to colour customers, because there were so few colour sets. And of course nobody would buy a colour set if there were no channels for it! Also, broadcasting the same thing in colour and B&W separately would need two separate channels, and there are only so many different radio frequencies available. Broadcasters in neighbouring areas can't use the same frequency as local broadcasters, cos they'd interfere in locales where the two stations, on one frequency, were both recievable. So there's only so many frequencies to use. And VHF frequencies are good cos they travel a nice distance, and round corners and between buildings (to a fair extent), where higher frequencies wouldn't. And lower frequencies couldn't carry as much information. So VHF it had to be. Then later UHF. So all-in, a new colour TV system would need to work on B&W sets, the ones customers already had, and had owned for years, without the colour producing any ugly effects on a B&W set. No effects at all. They did this by transmitting the picture, rather than as RGB, as chroma and luma. Luma is the same old B&W signal, for how bright each pixel on the screen to be. Chroma is what colour to make the pixel (but NOT the brightness, luma does that, just the actual colour). Also saturation gets stuck in there too. Modulated on a separate signal called the "colour carrier" that was added just above the B&W picture. This complete signal, B&W luma + chroma, transmitted out, and B&W sets didn't have circuitry to even look for the chroma carrier, so it had little effect. Sometimes though in a very strongly coloured signal (like kids' TV for a big offender!) you might see little fizzy dots around the edges of strong colours, but that's the limit. That's caused by the chroma carrier bleeding over into the luma. Wasn't a big problem, in an otherwise pretty good system. In 1954! Anyway this chroma carrier, a signal modulated onto a carrier frequency added onto the B&W pic... if the B&W picture, the luma, were to contain very particular patterns, those patterns, since it's all waves, and waves have frequencies, might coincide enough with the chroma carrier that the chroma circuit would recognise it and try decode it as colour. Of course such a pattern would rarely exist. But an on-off-on-off pattern in a luma signal, looks a lot like a wave in the overall signal, and the right thickness of stripes would produce that. So that's what the Apple II used for their colour system. On-purpose, for the main graphics. Lousy! The Atari 8-bits could do it. And the IBM PC too. Just send it some vertical stripes and that frequency would permeate into the signal, so much that a composite monitor would see it as a colour carrier. Et voila!
[more, yet more!] Composite monitors took a standard NTSC video signal. Except ones made for PAL countries. They connected just via a 2-pin RCA connector, in fact the same one still used by TVs for the same feature. Until HDMI replaces it, but most TVs still include it. The only difference from a broadcast signal from an antenna, apart from it being stronger, is that it's not modulated onto a radio wave. Which they have to do in order to transmit it. Same way sound is modulated onto one, for radio you listen to. Composite monitors weren't just made for IBMs, in fact I don't think IBM made one at all. But they were used for watching actual video, mostly by people in video editing. And also for other computers of the day. Security cameras too, though you'd be lucky to get a colour one. So it was a good choice on the CGA card for a popular format. "Popular" in a time when basically nobody had a monitor of any type, at least. The other monitor socket on CGA is the 9-pin one, for a digital socket with separate R, G, and B signals, and one for "Intensity" which sets half-brightness. That's why half the PC text-mode colours are half as bright as the others, and why they're the 8 possible combinations of R G and B. No composite or chroma sub-carriers here, so no artefact colours, no fun! On the good side you'd take longer to go blind trying to read text on it though. What DID work on composite AND digital monitors, was the other CGA trick used here. Also used by some old games. Pseudo-graphics in 16 colours. Basically, text mode is 80 columns of text, right? You can choose the colours for foreground and background, per-character. And one of the characters available is the half-bar. A rectangular block half the width of the character. So if you set foreground red and background blue, that character will have it's left-half red, right-half blue. So that's half a character for 80 characters, 160 pixels across, respectable! Beats the Atari 2600 already! Then secondly by sending the right commands to the video chip you could change from 80x25 character text, to 80x100. Instead of tiny squashed characters, it used only the top 2 layers of each character. So fill it with half-bars, use foreground and background for each half, and you have 160x100 in 16 colours! That's good for the time! The guys behind this demo were messing with that... and wondered what if you didn't use the half-bar. Perhaps the tiny details of each character would provide a signal like that stripes do for artefact colour. And apparently they do! So using certain other characters gives other results. This, I read about when reading about this demo, I think it's their own trick. And that's that! Extending the limits of crappy old hardware by being really clever! Hats off lads!
I'm so flattered by your interest in this that I'm not sure I can reciprocate with a sufficient reply, but thank you! Work on this demo actually started in the late 2000s, and in 2013 we started coding effects. The 3 months before April 2015 when the demo was revealed was where the bulk of the work went, but we had been programming little tests for many years earlier. While artifact NTSC colors have been in personal computers since the late 1970s, the main innovation of the demo was figuring out how to control CGA such that we could distribute bits across the carrier such that we could unlock 1000 colors, which I don't think any other platform of its era (1981) could do. Doing this required creating our own video modes that were very carefully timed by manipulating the 6845 registers with the CPU on every other line, as well as avoiding contention between memory accesses by the card vs. by the cpu.
@@JimLeonard You pre-reciprocated by writing the demo, mate! Did any one of you write in detail about your artefact colour use? Distributing the bits!? No idea what that means but I'd like to learn. Particularly I was sure you could only mess with NTSC chroma as the pixel itself was being drawn, and you only have so much time to do that. So even if you mess with the colour burst (like the Apple ][ did for it's amazing SIX colours!) you can still only get a few colours after that per line. You had to bit-bash the 6845? Impressive! To do what? Manually figuring out the RAM contention too is impressive (oh, it's all impressive, just assume I said that everywhere!). So you'd need the 8088 and 6845 manuals along with the IBM PC reference from IBM? And nothing else interrupting the CPU and throwing it all off. Apart from the timer I suppose that's n no problem if you don't access the disk drives or other hardware. Disable the keyboard interrupt. I can't remember if anything on the PC used NMI but that would have ruined it, right? Surprised you didn't need an analyser wired up to the ISA bus actually. The PC Speaker driver for Windows 3.1, beloved in our college for playing Beavis and Butt Head samples through, had an option to disable all interrupts during playback, otherwise you got constant clicking and buzzing. So the whole machine froze during your sample. You could do that back then! Again pardon my rambling, if you've written about all this technical stuff that'll shut me up for a while as I read it. Was it you who did video playback with the same system, or am I thinking of somebody else? They got real-colour video on an XT.
@@greenaum Yes, I did a few video systems for XTs :-) As for your technical questions, they are all answer using the technical explanation link in the video's description. Fun fact, reenigne DID create an analyzer, but that was after the demo was finished, so that he could more accurately write the cycle accurate emulator used in 86box.
@@JimLeonard Ah I just read that 8088 Domination is ANOTHER one of yours! You just don't stop! Fancy learning any other systems? The ZX Spectrum was the computer of much of British youth. It's directly responsible, from it's cheap price and therefore ubiquity, for why there's so many programmers and therefore games houses in Britain. It has limited graphics, 256x192 with 8x8 blocks of colour/ Caused "colour clash" when a sprite walked over a differently-coloured background. "Sprite"? Yeah, software, of course. Sound is a 1-bit beeper, on or off, software. Still, games soon enough started having sound effects and music during play. Very clever interweaving of code. Anyway it's very popular, and more importantly similar to the old PC in it's graphics, and particularly sound Fancy doing a demo on one of those? People have done, and some very impressive graphics. Oh, and you can override the 8x8 colour cells into 8x2 by very quick colour-switching in software. People even eventually wrote GAMES that run in 8x2, which is amazing when the CPU spends most of the time flinging bits at the screen RAM. Ta Jim, best of luck with whatever crazy schemes you've got, demos might not get much public attention, but their intended audience know what goes into them and appreciates the work and genius. By "intended audience" I of course mean geeks and weirdoes. Hey what about the Gameboy? All sorts of weird primitive systems you can abuse til they scream music!
If what I thought I knew about CGA could be this wrong, I just don't know what I can believe anymore. My entire reality could be a lie. I need to go comfort my Amiga while I rethink existence.
Apple II, Atari 8-bit, Tandy CoCo, Sega Genesis(probably the last platform it was useful on)... Anything with a suitably high resolution and a composite video connection can do it. It wasn't an unheard of technique on CGA back in the day, though this definitely pushes it farther than is normal.
@Channel07 As an ex-professional game dev, usually game assets goes _roughly_ like this: * 75.0% 2D + 3D Assets (Geometry + Textures) * 24.9% Audio * 0.1% Code Or in the case of Titanfall's bloat on PC: * 35 GB Audio (uncompressed!) * 13 GB Textures * 0.1% Code
Ho-lee nuts
Lazy Game Reviews Hah, glad you saw it already. Immediately thought of you..
Lazy Game Reviews If there's anyone out there who can get this running on a real system, it has to be you!
pigpen This was run on a real system and captured via composite. The demo won't run in emulators right now. It breaks them all, even DOSBox and PCem.
Seeing that you commented on this made me so happy lol
+pigpen LOL emu-lamer :)
It's not even remotely hard ... just needs very specific hardware in particular.
Being a music person, I'm most impressed with the shit you can do with the one-voice beeper.
+agogobell28 Spectrum 48K has a one voice beeper and that can produce some amazing music, Chronos is incredible
+retrogamer33 on PC beeper only square waveform is supported, and only control for output is setting the frequency, and of course you can silence it (if you don't it plays at that frequency until some other program changes frequency, or until powering down - I'm assuming spectrum had a bit more of ways to control it?
I know that, I was just pointing out that the Spectrum beeper can produce some amazing music
I was not certain about your knowledge of limitations of PC speaker, so I wrote that tiny explanation just in case, as I was really interested to ask about the assumed differences between it spectrum 48k's sound generation.
Like was the speaker just directly accessed and thus software controlled, or was there, as I would guess, a sound chip that controlled the speaker, and software must access and controls the sound chip - exactly like with C-64, but different features, limitations and capabilities?
If there's link(s) to information of this, I'd love to read...
Is there different waveforms? Can you set attack, sustain & decay to do different "instrument sounds", or use filters like hi/lo-cut, etc. and all that information of how was the nice sounds of it's single tone speaker (sorry if that was incorrect, can't recheck while commenting on phone) made?
If you do reply with any kind of information, I'll be very thankful :)
Let me chip in here. While the PC's timer chip could be programmed to output a square wave to the speaker, the Speccy's speaker could only be controlled by the CPU directly. Producing a square wave took most of the CPU power. And to produce different frequencies, you had to count CPU cycles to flip the bit at the right time.
If an 8088 can do this, then the singularity can begin on a Haswell.
If the singularity can begin on a Haswell, what d'you think could happen on a Coffee Lake?
you'd have up to a 14% bigger singularity on the Coffee Lake, duh
@@zangetsu6638 It can bloi the kettle for me - and make the drink :)
@@stashymane yes, that's the joke you missed xx
@@BenM64 Ryzen threadripper comes along and stomps on Coffee Lake's crapness
Incredible. I watched this quite gleefully.
@Brad Sanchez I see what you mean, but back then they didn't have cross compilers running on machines 30 years from the future. ;) And they didn't have google, stack overflow, nor github. Imagine trying to do this if you have to go to the library just to get a book about the 8088 instruction set. ;)
@Brad Sanchez haha, sure. And what we had much more of in the '80s: time.
Wow. From a technical standpoint, absolutely mindboggling that you achieved that on an 8088... puts Second Reality on my 486 to shame...
2nd reality was still a very decent demo :) *old love never dies*
probably eating a lot of clocks.
as someone who's currently writing a demo for an 8088 based system that doesn't even have system memory wait states i aspire to be magicians like them
Computing technology grew so fast that software had to get tugged along with it, not promoting things like optimization and learning to fully utilize what was available. Makes me wonder how much we missed out on because some things just didn't get experimented with and optimized to its full potential, or even near it, before we were onto a new chip or hardware standard. What is even more interesting to consider, where would we be now if we could have had those software advancements with earlier hardware.
I love that there is a community out there still programing on these classic platforms. Great demo.
For getting a slight impression, on what we are missing, because of the lack of optimization I recommend you watch or try yourself '.kkrieger' from '.theprodukkt'. (Both written correctly!)
While it doesn't look too impressive nowadays, it was back then in 2002, because it's an ego shooter using just 64KByte.
Yeah optimization is heavily missed. That's why I mostly play old games (although some make CPU usage max out one of the cores for no reason) I was taking a look at Rocket League, an interesting new game multiplayer only and a few maps. It asks for 7GB of disk space. Why why why
@@FeelingShred Disk space? Mostly b/c of textures and those ain't able to "optimize"-away. But I fully agree on the general mindset of optimized code in general. I wouldn't even want to know how many ressources win10 is throwing out of the window just for getting stamped OK if it is halfway stable merged bunch of code... not mention some gaming engines (cry engine e.g.) which is more like turning your pc into a heater than gettin it to an efficient realtime rendering......
Imagine coming back to old machines in the future and blowing people's mind
What on earth could we do with today's machines if that was possible back then??
1024 CGA colors?
1024 CGA COLORS!?!?
GREAT DOUBLEJUMPING SCOTT
*runs around like a maniac*
CGA composite color blending i.e. uses composite video's blur design flaw to mix neighboring pixels to create additional colors.
@@valenrn8657I guess this is one of those cases where you say;
*It's not a bug, it's a feature !*
This is truly masterful, I don't know what to be more impressed by, the multicolour CGA graphics or the digital sound coming out the PC beeper at the end. It's all amazing. I remember hearing a 4 channel mod file played for the first time out the speaker of my 386PC and even then I was totally blown away.
Well in theory it was always posssible. Just shift the wave file 2 bits right, ad all 4 files together, snip it to 8 bit then just post it to the PC speaker buffert (if i remember corectly the beeper buffert is 10 byte long. And if you do it in say 8Hz that is pretty typical, you have to post it 800 times a second... that is doable.. but.. well your code have to be very quick to interupt.
@@matsv201 There is no PC speaker buffer. The PC speaker could only be toggled from in to out through a single bit on IO port 61h. To play digitized sound you had to use a PWM technique and do very high frequency writes to the port and treat the PC speaker as a 1-bit DAC. There was no hardware to assist you, so you had to do these writes directly in your code, timed through interrupts or counting clock cycles.
I thought this was awesome, got to the end and thought 'they cheated and were playing that MOD through a soundcard!'
Then I realized they were pumping that through the PC speaker. That's some serious black magic, and makes the whole thing even more awesome!
oh, I remember noticing somewhere around 1995 a PC version of some tracker (can't remember the name, maybe impulse tracker 2), had among the usual ones at time, sound blaster 16, gravis ultrasound, etc., also support for passing through PC beeper - it sounds awful when compared to actual PCM, but amazing for something coming out of just PC speaker :)
And those trackers had the advantage of running on systems 5-10 times faster.
+Jim Leonard Indeed, I should've chosen my words more carefully as I didn't mean to say this wasn't anything new nor special because I saw a tracker on Pentium 75MHz do it :)
My point was the black magic wasn't playing MOD through PC beeper in itself, but doing it on 8088, and not only that, but doing it while also simultaneously doing all this very hardware intense (and impossible by technical specs ;D) stuff, and as if that magic's not black enough, it's (the music) played in sync with that "other stuff".
So I really meant to point the attention of readers to what's really amazing about the player, just forgot to write anything, except that it wasn't that playing PCM audio through beeper was something new, without including what it is that made doing it here very special :)
Sorry bout that.
@@robsku1 Fast Tracker II is the one you're thinking of. I just checked in DOSBox and v2.09 supports Ultrasound, Sound Blaster, Soundplayer, and PC Speaker in either single-bit or pulse mod modes. Of the speaker modes, pulse-mod sounds the best, but is on the quiet side, while the single-bit mode sounds terrible, but is a lot louder. Soundplayer is just an 8-bit LPT DAC, ala the Covox Speech Thing. Sounds almost as good as the sound cards, aside from a slight crackle that doesn't show up with the cards and gets worse when you move the mouse.
@@Roxor128 thanks for the informative response :)
It's absolutely mindblowing what some people can still do with this old hardware. Fantastic.
SICK! If everybody would take such care in squeezing out what's possible in the hardware, we wouldn’t be needing new chips since 1996
its a demo not feasible in a game.
@@ChickenPermissionOG I don´t quite agree. There are several things here that could be ported over to games just fine
@@ChickenPermissionOG OK but that's not what he was saying.
From now on I am doing all my LLM training and 4k raytracing on a Pentium Pro
Imagine popping in a time machine to the guys designing/running CGA hardware for the first time and showing them this. :)
They wouldn't get the back to the future reference, lol
Came here after reading about it in Planet X3’s manual and DAMN! This is impressive... all of it. Having started my computing days with an 8088 and CGA, this looks like wizardry. Never knew this was possible... more please!
Absolutely incredible, you guys did a fantastic job and deserved to win. Really really cool!
Thanks!
now that's crazy impressive
Each section made my jaw drop more and more. The 1k colors part is super cool in particular, getting that out of CGA.
I come from 8 bit guy and your contributions with Planet X3, Greetings from Venezuela.
IBM PC Master Race
neoqueto Filthy Commodore peasants
@Neb6 No. The Atari 800 can only display 2 colors in 320 x 196 pixels resolution.
@@Parvex if you use the standard modus, yes you are right. But like this demo is full of tricks, the Atari has his own box of tricks (DLI for example). None the less, I don't care which was the better computer or so. I really enjoy to see what people nowaday can do with old hardware and doing things we never dreamed of back in the day :)
Hello! I came here to talk about the Demoscene
Your team and other Demoscene groups did an awesome job! I'm a very young adult and your demos made me really love the Demoscene and the Retrogaming!!
I really congrats you and everyone who contributed to the Demoscene. Your work is amazing and the music keeps in my head and will keep forever! I am amazed by the technical aspect of the demos and machines, I really would like to code some programs one day, even if I don't even know how to code a simple program for now. But I got a lot of decades to go ahead!
Thank you again for your team and every Demoscene groups for your amazing work. I hope that you inspired a lot of people other than me! ❤
That's wonderful to hear, thank you! I hope you have the opportunity to visit a demoparty, as they are wonderful experiences.
@@JimLeonard Visit a Demoparty? This is my dream 😍
@@JimLeonard Also, do you have any contact or discord server about Demosceners? I have too many questions, I am so curious
@@kaerucraft7100 I would start by browsing pouet.net and reading various BBS posts, although there is a lot of veterans there and a lot of it might not make sense. Also, older people tend to be "angry" and dismissive, so keep that in mind. Also find some pouet.net demos that have done very well and read the comments under them. If you're ready to join a discord, I believe discord.gg/XBgbQd22 is the most popular one, but make sure to introduce yourself as a beginner so that people can respond appropriately.
Having thoroughly enjoyed my 4.77MHz with CGA in the 80's, I absolutely enjoyed this. Well done.
You can teach an old dog new tricks. Very impressive and well-deserved pat on the back!
Saw this live at Revision and it blew my mind, but more than anything it's the music that sticks with me. So funky!
Are these the best graphics and sounds ever to come out of an original PC? Mind bending work, kind of unbelievable.
Jaw droppingly _amazing_. Just _OMG_. I can't believe it, but it's there. Right before my eyes.
Awesome! Who would've thought such old hardware is capable of _this_ sort of craziness?! If only today's programmers could be as super-talented and competent as these guys; then we'd have much better optimisation, more competently-programmed games and fewer cheap console ports, for a start. Amazing work!
I cannot stop watching this, it’s so beautiful. I love this, good work.
Congrats guys! It's amazing what you managed to get out of the good ol' PC. The graphics in particular are friggin' killer!
The IBM PC has been officially pimped.
I might have to buy a ibm cga card and try this on my pc now, damn this is well done
I wonder what would I need to connect the CGA to generic CRT monitor or TV (preferably, finding a CGA monitor would be too hard; I like collecting, but I'm barely an amateur, I rarely hunt for much, like with Macintosh SE/30 I got free from neighbour but was too late to save the keyboard from garbage dump, and I haven't even tried to find one), with antenna, SCART and... oh, composite, Of my old TV works. I have no idea, but what about flat screen tv, does that produce the same colour "errors"? And it has no composite, at least not separately, but one source it can use is "component", which has several similar connectors, and I've heard that it can support various similar systems that don't have all of the connectors, but even if that's true, I guess that has naught to do with composite?
Then what about the old way of using tv's analog antenna connector, it was the default for c-64 and most 80's micro computers, and for Amiga 500 you could buy a device between it and tv to connect it via antenna connector, which was probably so used here because Finnish tv's didn't nearly always have composite, and SCART wasn't yet in everyone's tv's.
So is there a converter from composite to tv antenna (PAL) that's cheap, and does it no bad to the colours?
Other ways? Yes, the old TV has composite, but I'm unsure if it works.
You basically just need a bit of luck. Most TVs have composite in either via cinch connectors or scart (or both). Quite a few TVs are dual-standard, so they can take both NTSC or PAL composite signals. You probably have more luck with an LCD TV than with CRT, because it's easier to run an LCD at both 50 Hz and 60 Hz than it is for a CRT. For what it's worth, I used a Samsung LCD TV during development of this demo (it's a 'PAL' TV, I'm in a PAL country). NTSC artifacts work fine on it.
On some TVs it will work, on others it won't. I have a newer Samsung LCD TV that only takes PAL composite.
By the way, there was an optional antenna modulator module that can be plugged onto a CGA card, but I think they're extremely rare. And then you need an NTSC-compatible TV tuner, so you really do need an 'NTSC' TV, as most TVs only have a single TV tuner on board.
AIUI you'd need a complete IBM PC 5150. The timing is exact in this, so it only works on the actual PC. That's why I'm watching it on TH-cam and not DOSBOX or the like.
@robsku, any composite monitor would be suitable for CGA's composite artefact-colour mode. All monitors used to be composite, way back when. The popular Commodore monitor, forget which one, supports it.
Actually any TV over a certain age, too, supports composite through the "video" port, the single RCA connector.
If IBM hadn't chosen a resolution of 320, an exact multiple of the NTSC colour clock, and used a cheap crap NTSC colour modulator, then that wouldn't be possible. And many of the old CGA games, which took advantage of artefacting, would have been stuck in utterly abominable cyan-on-bloody-magenta.
Honestly no idea why IBM chose those two awful colours. Or why games programmers used that palette. It has black and white in it, but the other 2 colours are painful to see. The alternative was blue, green, red, yellow, much more soothing. Or even a third scheme with a bit of a combo.
@@Scalibq Most modern TVs will tune in the American VHF fine, as well as the UHF other countries use. They're all made in the same factories in China now, and it's cheaper to just put a universal tuner in, and control it with software.
Finding an IBM CGA RF modulator will be almost impossible. But I can't think why a generic one wouldn't be fine. Give it 5V from the keyboard port or a disk drive power cable. That's if your TV doesn't support composite, which it probably does.
Read through the full explanation of how each part of this works. Understood most of it. _Still_ think that it's essentially voodoo. Amazing work.
great experience watching this... true hardware exploration, refreshing muzak, and superb gfx to sort you out - Executed with attitude and style.. cheers!
Wow! Its fun to see renewed interest in NTSC artifact video modes on multiple platforms at roughly the same time (See Bill Buckel's BMP2DHGR on the Apple II) . That blurry composite video we all used to complain about was capable of doing something useful all these years!
I applaud them and their dedication to their craft.
*gobsmacked* This is easily one of the most interesting and well-put together demos I've seen in ages! Grats to the whole team on this impressive piece of code wizardry! =^.^=
unbelievable!!! I've no more words for such a mastery!!! please keep going, really looking forward to see those techniques applied to real programs/games, and difficult to hope for more but... who knows!!! BRAVI!!!!!
Jim you are true computer enthusiast, spending all this time on a 40 yo pc, doing what the og programmers should have been doing back in the day.
How is this running on a CGA card!? And the end music? Witchcraft!
I don't think the end music is actually running on the one-voice beeper
@@ryanpenrod1859 It most definitely is. It's just using a technique called PWM to produce much more complex sounds at the expense of eating up 99% of the cpu's cycles. It was also used by music trackers such as FastTracker 2. A few games on the ZX Spectrum did it too, although the speccy was more limited on memory
@@redpheonix1000 Cool, thanks for clarifying. That's what I meant I suppose, it is using direct CPU modulation instead of the usual timer-driven speaker inputs, aka square waves I guess.
CGA: 1024 colors
VGA: 256 colors
CGA Is officially better than VGA
EDIT: I read about how it worked:
CGA Composite/Artifacting:16 col
CGA Text mode w/ Max scanlines=1:16 col
CGA Pallete register:4 col
16 x 16 x 4 = 1024 col
@@ryanpenrod1859 It's using square waves, except instead of a timer chip controlling their length, it's done with software instead. The CPU can still only switch the speaker on or off. But with clever techniques and some physics, you can PWM several channels of "analogue" sound through it. Still only 1 and 0 though.
Actually modern CD players (if they still make those) use the same technique in their DACs, at least the "1-bit" ones do. Just flipping one bit, very fast, several MHz for a 44.1KHz signal. The sound is better, and it doesn't rely on carefully set-up analogue circuits like an ordinary DAC. Delta-sigma is one method.
2:23 Nice reference, it reads like something in a dream! Very impressive demo... wow!
If an 8088 with CGA can do this, then my old crappy laptop with Intel Celeron N3050 laptop with Intel HD Graphics can run a demo with real life graphics, raytracing at 60FPS!!!
Jeezus!
i had a CGA 8088 for years and thought i know what a CGA/XT can do....
/bow to the king
This is beyond awesome !
WOW!! CGA pulled ti it's limits! Amazed!
Dat Chiptune.
If they can do something like that on old hardware, what can they do on modern ones?
in b4 Tron.
That's the power of Jake "VIRT" Kaufman and others, man!
Wow, truly inspiring work!
>This demo breaks all emulators :-)
Remember this was said nearly 5 years ago.
Yes... and it took our emulator core in order for 86box to run it correctly ;-)
Just watched this with my dad, at 2:34 and 4:38 his jaw dropped and hit the floor.
I was not expecting you to heart this holy frick thank you! This demo is my personal favorite!
Difficult to believe. I am suitably impressed.
Stunning artwork, exceptional programming feat. Please let us know more about the technical background of all the hacks.
Possibly the greatest technology hack ever.
I got a commodore pc-10 just to get the message:"thank you for playing on original hardware" ;)
Nice :-)
Classic computer effect's with picture art-machine also very change background scene and position image in demo is positive nice for culture eyes for view, for hear sound music. 🎞👏😇😯😑⌨
I don't normally comment on videos etc, but, holy shit.. Totally mind blown.. I wish I still had out old IBM so I could boot this baby up.. I may have to go an hunt one down just to try it...
If I saw this back when I was a young'un... Jeez
Yeah, just give them a few more days and they do a 256 color demo on Hercules. With a green monitor. With stereo sound from the PC speaker!😂
Awesome music! Totally crazy effects!
This is black magic voodoo of the highest order.
And all this time I thought 64 colors on EGA was a feat. Impressive!
Very impressive ! Excellent work !!
На досбоксе на последнем кадре (авторы) - адское мерцание. Вот как вы достигаете много цветов!
Amazing.
Great things are possible to the masters of disciplines, even seemingly limited ones
.
No one use the PS3 to its full potential, and no one used CGA graphics to their full potential until recently (in this demo).
Having said that, despite how impressive the polyphony in the music from a monophonic one voice sound card was, the SID is a better sound card, and the same music would have sounded better in SID (plus, all of the tricks that you used here, I assume can be used on the SID, too).
Anyway, 10 / 10, great job. faithInHumanity+=200;
Edit: Wait, did that sound card play the music at the end, too? Holy bloody shit, is it really true? I don't know what to believe. Can some one who knows tell me the answer?
Yeah, the end credits are played on the PC speaker, with a really tight code, and I mean REALLY, basically using almost every single CPU cycle that isn't pushing the text onto the screen.
Here is a writeup from the author: www.reenigne.org/blog/8088-pc-speaker-mod-player-how-its-done/
Basically a SID-like (due to the obvious limitations) .MOD player (albeit with some pre-processing to adhere to the bandwidth limits) using assembler sorcery in many clever ways to manage that on 8088 with only a puny PWM-controlled beeper :)
Wow! Insanely well made!
Wow, amazing job. Great work.
Impossible! You're not supposed to do that! Well done!
F***ing Demo Coders, this is the cream of the cream, this is hacking in the original way, pushing limits and boundaries.
Kudos!!!
OH WOW
well done, great work!
Scroll back up, you're missing out
Or maybe not! The music alone is badass!
incredible, wished that 35 years ago
The music should be available on streaming platforms. I only open the video now to listen to the music.
I think Team Dai-Gurren found some new members, 'cause they just did the impossible.
This is true hacking at its finest. Amazing work!
PCem (emulator) can *almost* run this 100% correctly. It has a 11% "metric cycle count" deviation, flickers like hell at 4:38 (screen resolution changes) and freezes at the beginning of the Credits scene. The timing also feels very slightly off.
next do chatgpt
Funny you mention that; I learned last week that John Walker implemented a tiny neural network on a C64 back in 1987.
@@JimLeonard Andrej Karpathy made a nice tutorial using the Python NN libraries for Python ("Let's build GPT: from scratch, in code, spelled out."). Reducing the training set to a minimum (children's books or simple number sequences) might do the trick.
@@ClemensLode If only python were available for 16-bit platforms
VOGONS crew, represent! :-D
Greetings from Reddit /r/retrobattlestations!!
Prepare to be CRUSHED.
This is the same series of cpu that power the raiden ar arcade machines though. Raiden uses an nec v30, which is a revision of v20 cpu, which is just a 8080+8088 in one. Also, the wonderswan uses a v20 cpu as well. The gameboy uses a customized and enhanced variant of the 8080 cpu which is labeled as sm83
Yes, but all of those systems have additional graphics and sound support chips. All of the graphics in this demo are created by the CPU manipulating individual bytes of video memory. No sprite hardware, no tiles, no redefinable character sets...
@@JimLeonard yeah, that is impressive, but this cpu is really powerful. The zx spectrum didnt have any support chips for graphics either and that has a weaker z80 cpu
@@mariowario5945 Which is why demos on the ZX Spectrum are similarly impressive. (To be fair, ZX Spectrum has a redefinable character set ;-)
@@JimLeonard what's the most impressive zx spectrum demo you've seen?
This is INSANE!
8:06 HEY! I'm one of those guys! At the way bottom above Phoenix!
Watching this 35 years later makes me instantly want to boot from a floppy 🤓
Ok when does the 3 hour documentary come out?
I'm sure reading trixter.oldskool.org/2015/04/07/8088-mph-we-break-all-your-emulators/ and all of the pages it links to will take 3 hours; there's your documentary :)
Amazing link, thanks. Bookmarked!
What those guys did is great. I still think game programmers got lazy at late 90's and we still never saw the full potential of the Pentium 3 for example. If Quake could run in a Pentium 166MHz, I think much more could be milked from 600/700/800MHz CPUs. Even the Playstation does amazing stuff with only 33MHz
Consider. Me. Stunned.
What makes the 5150 great is its expandability. Why not outfit one with a Professional Graphics Controller and a Music Feature card (or two, the documentation says a maximum of two is permitted in a system, although I'm not sure what that would do. I suggest first-party hardware because with the variety of stuff out there for the machine there's no other way to keep it in order.
You can fit up to four Music Feature Cards in a system, actually, for up to 32 voices and 4 midi in/out/thru ports.
Wow, this is amazing :O
I find it funny that the "Ho, what's this? An IBM PC from 1981?" message also appears if you run this in 86Box.
So this is just awesome Jim. Really sweet stuff. Can't wait to read the write up. This is clearly what Andrew hinted at in a recent email exchange. I take it you are in text mode with the colurburst bit enabled and some type of 1/2 height character cell? What i love is the perfect match up of the composite artifact pattern to the target image. Converter has to be based on a calculated NTSC output - wow - fun optimization work. What was the oversampling rate of the NTSC simulator? (Or did yu guys get there another way?) Love the polyphonic at the end as well. Awesome - really great. The last thing I love about it is this: th-cam.com/video/9VPn5gkG_Qo/w-d-xo.html
Yes Jim - it would make an awesome screen for a demo. :)
Imagine showing this to the IBM engineers shortly after XT was released.
They would increase the price.
Holy shit, how can this be CGA?
Is the module file being used in the credits published anywhere? Getting all protracker effects at a decent sampling rate is extraordinary work.
Lysergesaure1 It's now online and linked to from the technical blog post about the MOD player at www.reenigne.org/blog/8088-pc-speaker-mod-player-how-its-done/ .
Thanks! You are awesome!
There damn better be an article series on this. How the F? =)
2 man-years of work! If it had taken 2 years it would have been impressive! But between 6 of them, that's.... erm.... dammit this is when some device to calculate mathematically would be useful... 4 months! Does that include the original research? I suppose it does! Although the techniques, namely artefact colours, and pseudo-graphics 16-colour mode, were both long-known in the PC world, putting them together like this still deserves a shitload of credit, and especially for the effects achieved. Artifact colour had been used on PC games since the early ''80s, Ultima II is the example I can best recall. I didn't have a PC then of course, but I've always been an Ultima fan so bought the compilation years later. Any CGA game where the colours are in weird vertical stripes, often missing half of the stripes, is probably using artefact colouring. That is, there's no other reason to do graphics like that.
You can look it up yourself, but basically it relies on the NTSC encoder on IBM's CGA card being a bit shit, cheap and shoddy. Although IBM choosing 320 pixels across, exactly half of the 640 pixels of NTSC (any multiple would have similar effects) also helped. Well, "helped". It was an unintended side-effect, pretty sure IBM never planned on anyone using it on purpose. It meant that in 320-pixel modes like CGA's 4-colour graphics modes, alternating pixels in stripes would show up on a composite monitor as extra colours, solid not striped. Basically the frequency of the signal, of lots of stripes, is a similar frequency, or related, to the colour-carrier frequency.
This goes back to NTSC television back when they were inventing colour TV. In particular they wanted a system that would still produce a picture on old black and white sets, this being the 1950s. You couldn't start a channel broadcasting just to colour customers, because there were so few colour sets. And of course nobody would buy a colour set if there were no channels for it! Also, broadcasting the same thing in colour and B&W separately would need two separate channels, and there are only so many different radio frequencies available. Broadcasters in neighbouring areas can't use the same frequency as local broadcasters, cos they'd interfere in locales where the two stations, on one frequency, were both recievable. So there's only so many frequencies to use. And VHF frequencies are good cos they travel a nice distance, and round corners and between buildings (to a fair extent), where higher frequencies wouldn't. And lower frequencies couldn't carry as much information. So VHF it had to be. Then later UHF.
So all-in, a new colour TV system would need to work on B&W sets, the ones customers already had, and had owned for years, without the colour producing any ugly effects on a B&W set. No effects at all.
They did this by transmitting the picture, rather than as RGB, as chroma and luma. Luma is the same old B&W signal, for how bright each pixel on the screen to be. Chroma is what colour to make the pixel (but NOT the brightness, luma does that, just the actual colour). Also saturation gets stuck in there too. Modulated on a separate signal called the "colour carrier" that was added just above the B&W picture. This complete signal, B&W luma + chroma, transmitted out, and B&W sets didn't have circuitry to even look for the chroma carrier, so it had little effect. Sometimes though in a very strongly coloured signal (like kids' TV for a big offender!) you might see little fizzy dots around the edges of strong colours, but that's the limit. That's caused by the chroma carrier bleeding over into the luma. Wasn't a big problem, in an otherwise pretty good system. In 1954!
Anyway this chroma carrier, a signal modulated onto a carrier frequency added onto the B&W pic... if the B&W picture, the luma, were to contain very particular patterns, those patterns, since it's all waves, and waves have frequencies, might coincide enough with the chroma carrier that the chroma circuit would recognise it and try decode it as colour. Of course such a pattern would rarely exist. But an on-off-on-off pattern in a luma signal, looks a lot like a wave in the overall signal, and the right thickness of stripes would produce that.
So that's what the Apple II used for their colour system. On-purpose, for the main graphics. Lousy! The Atari 8-bits could do it. And the IBM PC too. Just send it some vertical stripes and that frequency would permeate into the signal, so much that a composite monitor would see it as a colour carrier. Et voila!
[more, yet more!]
Composite monitors took a standard NTSC video signal. Except ones made for PAL countries. They connected just via a 2-pin RCA connector, in fact the same one still used by TVs for the same feature. Until HDMI replaces it, but most TVs still include it. The only difference from a broadcast signal from an antenna, apart from it being stronger, is that it's not modulated onto a radio wave. Which they have to do in order to transmit it. Same way sound is modulated onto one, for radio you listen to. Composite monitors weren't just made for IBMs, in fact I don't think IBM made one at all. But they were used for watching actual video, mostly by people in video editing. And also for other computers of the day. Security cameras too, though you'd be lucky to get a colour one. So it was a good choice on the CGA card for a popular format. "Popular" in a time when basically nobody had a monitor of any type, at least.
The other monitor socket on CGA is the 9-pin one, for a digital socket with separate R, G, and B signals, and one for "Intensity" which sets half-brightness. That's why half the PC text-mode colours are half as bright as the others, and why they're the 8 possible combinations of R G and B. No composite or chroma sub-carriers here, so no artefact colours, no fun! On the good side you'd take longer to go blind trying to read text on it though.
What DID work on composite AND digital monitors, was the other CGA trick used here. Also used by some old games. Pseudo-graphics in 16 colours. Basically, text mode is 80 columns of text, right? You can choose the colours for foreground and background, per-character. And one of the characters available is the half-bar. A rectangular block half the width of the character. So if you set foreground red and background blue, that character will have it's left-half red, right-half blue. So that's half a character for 80 characters, 160 pixels across, respectable! Beats the Atari 2600 already!
Then secondly by sending the right commands to the video chip you could change from 80x25 character text, to 80x100. Instead of tiny squashed characters, it used only the top 2 layers of each character. So fill it with half-bars, use foreground and background for each half, and you have 160x100 in 16 colours! That's good for the time!
The guys behind this demo were messing with that... and wondered what if you didn't use the half-bar. Perhaps the tiny details of each character would provide a signal like that stripes do for artefact colour. And apparently they do! So using certain other characters gives other results. This, I read about when reading about this demo, I think it's their own trick.
And that's that! Extending the limits of crappy old hardware by being really clever! Hats off lads!
I'm so flattered by your interest in this that I'm not sure I can reciprocate with a sufficient reply, but thank you! Work on this demo actually started in the late 2000s, and in 2013 we started coding effects. The 3 months before April 2015 when the demo was revealed was where the bulk of the work went, but we had been programming little tests for many years earlier.
While artifact NTSC colors have been in personal computers since the late 1970s, the main innovation of the demo was figuring out how to control CGA such that we could distribute bits across the carrier such that we could unlock 1000 colors, which I don't think any other platform of its era (1981) could do. Doing this required creating our own video modes that were very carefully timed by manipulating the 6845 registers with the CPU on every other line, as well as avoiding contention between memory accesses by the card vs. by the cpu.
@@JimLeonard You pre-reciprocated by writing the demo, mate! Did any one of you write in detail about your artefact colour use? Distributing the bits!? No idea what that means but I'd like to learn.
Particularly I was sure you could only mess with NTSC chroma as the pixel itself was being drawn, and you only have so much time to do that. So even if you mess with the colour burst (like the Apple ][ did for it's amazing SIX colours!) you can still only get a few colours after that per line.
You had to bit-bash the 6845? Impressive! To do what? Manually figuring out the RAM contention too is impressive (oh, it's all impressive, just assume I said that everywhere!). So you'd need the 8088 and 6845 manuals along with the IBM PC reference from IBM? And nothing else interrupting the CPU and throwing it all off. Apart from the timer I suppose that's n no problem if you don't access the disk drives or other hardware. Disable the keyboard interrupt. I can't remember if anything on the PC used NMI but that would have ruined it, right?
Surprised you didn't need an analyser wired up to the ISA bus actually.
The PC Speaker driver for Windows 3.1, beloved in our college for playing Beavis and Butt Head samples through, had an option to disable all interrupts during playback, otherwise you got constant clicking and buzzing. So the whole machine froze during your sample. You could do that back then!
Again pardon my rambling, if you've written about all this technical stuff that'll shut me up for a while as I read it.
Was it you who did video playback with the same system, or am I thinking of somebody else? They got real-colour video on an XT.
@@greenaum Yes, I did a few video systems for XTs :-) As for your technical questions, they are all answer using the technical explanation link in the video's description.
Fun fact, reenigne DID create an analyzer, but that was after the demo was finished, so that he could more accurately write the cycle accurate emulator used in 86box.
@@JimLeonard Ah I just read that 8088 Domination is ANOTHER one of yours! You just don't stop! Fancy learning any other systems? The ZX Spectrum was the computer of much of British youth. It's directly responsible, from it's cheap price and therefore ubiquity, for why there's so many programmers and therefore games houses in Britain.
It has limited graphics, 256x192 with 8x8 blocks of colour/ Caused "colour clash" when a sprite walked over a differently-coloured background. "Sprite"? Yeah, software, of course.
Sound is a 1-bit beeper, on or off, software. Still, games soon enough started having sound effects and music during play. Very clever interweaving of code.
Anyway it's very popular, and more importantly similar to the old PC in it's graphics, and particularly sound
Fancy doing a demo on one of those? People have done, and some very impressive graphics. Oh, and you can override the 8x8 colour cells into 8x2 by very quick colour-switching in software. People even eventually wrote GAMES that run in 8x2, which is amazing when the CPU spends most of the time flinging bits at the screen RAM.
Ta Jim, best of luck with whatever crazy schemes you've got, demos might not get much public attention, but their intended audience know what goes into them and appreciates the work and genius. By "intended audience" I of course mean geeks and weirdoes. Hey what about the Gameboy? All sorts of weird primitive systems you can abuse til they scream music!
Great work!
Nicely done! :o
if this is what a 4.77 MHz CGA machine can do i can't imagine what C64 or an 8MHz EGA machine can do
Holly ⭐️!?⭐️
Mind blown, wow.
The credits don't make it clear: who did which music (demo vs credits)?
+Greg Kennedy First part: Phoenix, second part (starting at sprite part): Virt, endpart: Coda.
If what I thought I knew about CGA could be this wrong, I just don't know what I can believe anymore. My entire reality could be a lie. I need to go comfort my Amiga while I rethink existence.
Colour artefacting like the Apple II?
Apple II, Atari 8-bit, Tandy CoCo, Sega Genesis(probably the last platform it was useful on)... Anything with a suitably high resolution and a composite video connection can do it.
It wasn't an unheard of technique on CGA back in the day, though this definitely pushes it farther than is normal.
Stay Forever Podcast sent me.
Hat down to you sirs.
My graphics driver actually crashed while watching this video. As in the latest AMD one.
LMAO
With all this on a 8088, makes you really wonder if current games are really tuned for their hardware
Daniel Witzel Meanwhile ARK Survival with all the DLCs is a bloated 192 GB pig. Lazy devs.
@Channel07 As an ex-professional game dev, usually game assets goes _roughly_ like this:
* 75.0% 2D + 3D Assets (Geometry + Textures)
* 24.9% Audio
* 0.1% Code
Or in the case of Titanfall's bloat on PC:
* 35 GB Audio (uncompressed!)
* 13 GB Textures
* 0.1% Code
My ears.
At least there were pretty colors.
Sounds were great