The original Sony PlayStation was a nifty console for its day; that grey box may have only had a 33 MHz MIPS processor and 4 MB of RAM, but for the early to mid 1990s its games were some of the best to be had. From the days when it would have sat under a family TV with a composite video or RF connection, you might expect that the PlayStation would require some form of converter box to drive a higher quality monitor. As [Wesk] found out though, present on the PS1 mainboard are all the required H and V sync as well as RGB video signals to drive a VGA monitor at 15 kHz.
It’s a wallow in the past for anyone who spent the 1990s using their SMD soldering skills to install modchips in PS1s, but it’s pleasing to find that those sync lines aren’t only available from tricky-to-solder IC pins, instead they appear on handy pads. Along with RGB lines from the normal video output they’re brought out via lightweight co-ax to a VGA socket that sits in a 3D printed bracket in the space where a removed system link port would have been. A small trim of the internal shield is requited to clear the new socket, leaving the VGA port on the back of the reassembled console looking for all the world as though it was installed in the Sony factory. Given how simple this mod turned out to be and the sharpness of the resulting image, it’s surprising that this wasn’t tried back in the day. Perhaps we were all too busy playing Wipeout.
While you’re idly rekindling your interest in a PS1, should you buy one then perhaps you’ll need a modchip.
Thanks [John] for the tip.
The problem with these mods, is that monitors supporting 15 kHz are extremely uncommon unless you grab your time machine and travel back to the eighties.
Next time you have access to an LCD monitor with a VGA port, try feeding it RS170 / NTSC / PAL timing. I have this hunch that support is not as rare as we thought, just undocumented.
I have tried that with evey tv I have ever owned that had a vga port including crt
None worked cause 15khz is not VGA
Would something like Sony BVM D24 be compatible?
PS1 outputs RGBS with sync on composite or luma unmodded, and the D24 will take it
The Amiga community knows about most of them.
Orrrrr there’s a wiki apparently.. http://15khz.wikidot.com/
and collected listings on Amiga forum..
https://eab.abime.net/showthread.php?t=85693
Sadly, many of the ones that work are problematic. And they’re becoming almost as rare as old multisync CRTs.
Macs of the era also put out 15kHz and many LCD were plenty happy with it
No Mac ever puts out 15 kHz video signal on its monitor port. They do have resolutions and timings that are different to PCs, but they’re not meant for TVs at all.
Macintoshes most certainly did not. They had some weird resolutions and timings, but the last Apple product to do a 15KHz RGB (csync) signal was the IIgs.
No the little 15 to HD 15 adapters are set to tell the mac to output 31khz only apple displays ran at 15khz and usually only the small – cheap ones
The Playstaion 1 has 2MB of main RAM, and 512K of video RAM. Where on earth does that 4MB that Jenny List mentions come from?
But perfect for the GBS-C diy upscaler which takes VGA as an input and then outputs HDMI ;)
There is not and was never any such thing as “15 kHz VGA”. VGA was 31 kHz. CGA, RS-170 and NTSC were 15.7 kHz. PAL is/was close to that too.
It must be RS-170 or whatever aussie equivalent component RGB mode. (SCART?) Or maybe even really CGA.
There did exist multisync monitors that could handle both CGA/NTSC/RS-170 and VGA timing though.
VGA means “analog RGB 0.7Vpp via 75Ω cabling with separate sync”. After all, we still used VGA ports even with SVGA cards and multisync monitors. Doesn’t imply much about sync rates.
You’re allowed to whine all you want about using “VGA” as shorthand meaning “HD15 connector with standard VGA pinout” but I don’t see what pedantry you think you’re achieving.
Ahh, the Humpty Dumpty defense: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean—neither more nor less.”
Using alternate definitions for standards demonstrates ignorance and confusion.
The VGA spec was pretty specific about timing. It didn’t just mean signal levels and connectors.
Ah, so the 15 years that people spent connecting multisync monitors to their Super VGA cards, they were not using VGA, because that wasn’t 31.5kHz hsync and 60/70Hz vsync. The connector is definitely not a VGA connector, because it doesn’t carry the right sync rates. Indeed, there was no name at all for what they were doing. They were instead required to spend 20 words describing the exact nature of what they were doing instead of something succinct. Got it.
No need to get knickers in a knot over this.
The OP clearly stated “native 15khz VGA.” There is no such thing. That’s all.
Of course the VGA connector can carry other signals, and multisync monitors support scan rates other than VGA. No dispute there.
Words change meaning over time.
Like people calling car wheels for rims, despite addressing more than just the rim of the wheel.
These days, when you say VGA, people tend to think of the connector first and foremost, and MAYBE then that it’s 0.7 peak to peak analog signal with two digital timing signals.
Rest is pedantry or ancient history to to those who haven’t read the full vga specs.
Yeah, if it has a VGA port and most VGA capable monitors accept it, I’d say it’s VGA
“Sharpness” isn’t exactly desirable for the low-res and low-poly PS1 graphics.
It looks better when you squint your eyes.
It isn’t the excessive sharpness that’s the real problem, rather the wobbliness of anything slightly moving.
But both are reasons I personally prefer to emulate PS1 instead of the real deal, as some modern emulators have filters to address the worst of it and also gracefully upscale it.
I was going to say this, although I have been surprised and delighted at how nice Rick Dangerous for the C64 looks on a 32″ TV with a Lumafix and S-Video.
Modern Vintage Gamer did a great YouTube about this wobble. Fascinating watch
4mb of RAM?
2mb RAM, 512k for SPU and 1mb for Video.
This has been known for a while, they are all there on the schematics but 15khz…
December 1994 is early 90s?
Someone posted this page in a reply to Wesk’s original post:
http://15khz.wikidot.com/
Oh that’s really cool! Got a thing that outputs 15Khz analog video with a dead monitor I’m trying to replace and having a spare LCD that I could use as a backup would be so helpful
If you want a small one, in car DVD headrest monitors seem to be not too hard to find used and cheap 6″ to 9″ and take composite, and some have RGB on a DIN connector or something. I hook up one to my N64 once in a while, or use flashback joystick games with it. They don’t do so great with an android box though, can’t read them LOL (Plus it’s hard to find any video to play as they all whine about no HDMICP etc) Haven’t tried with retroarch or similar yet, kinda sorta planning a mini arcade cab with just tv box guts, one of them and a decent joystick.
Was meant to be a reply, but here is fine too :)
If your monitor is okay with sync-on-green then all the signals are already on the multi AV socket on the back. Sony made a passive VGA cable for the PS2 Linux kit that also worked on the PS1. There were third party active adapters as well that split off the sync signal if your monitor wanted separate sync signals.
PSX doesn’t do SoG, at least as far as my scope was concerned, but you can easily pull the sync signal out of s-video luma/composite video with an LM1881.
And as one by one milestones are reached, this, together with a few other “advances” in rational, will eventually produce an add-on that will be available for soldering-plugging in, and together with some other not yet conceived miniature all-in-one upscaler-converter-linedoubler one will find that all it takes will be some €99.99 which in turn will over time drop to €49.99, and one will be able to connect it to 4k TV and play like it was always meant to be that way, with hint of smile and a thought in the background saying “oh yeah, why didn’t I thought of that”. Just like we “knew” for years that PS2 emulation will simply not run on pc or god forbid on an ordinary phone unless specs are through the roof, and look at it now. Technology indeed is moving at an unprecedented pace.
I predict all consoles from 1990 to 2010 to be available in all-in-one package running from one cable directly to 4k TV with superb picture quality. It will be expensive at first, and then the price will nose dive. Wait and see. A little bit of further miniaturised hardware and a handful of emulation will produce a new toy capable of previously thought impossible. Wait and see. Exciting times ahead.
Nice thing about 15 khz is that you can plug in a scandoubler and thus have your 31khz vga compatible signal.
Let’s set a few things straight here.
1. The title of this article is a misnomer. 15KHz is not a standard timing for VGA, and it is uncommon for VGA computer monitors to display it. Yes, there is a list out there, but it is quite small.
2. This is a ridiculous amount of effort, when he could have just tossed an LM1881 in the mix, to strip the CSync signal from the composite video or s-video luma signal that the playstation outputs. Heck, you could even just get PS3 component video cables and a guncon adapter(for the composite video,) and then you wouldn’t have to modify anything! Pretty much any monitor that takes in an RGB signal at 15KHz hsync will also support composite (combined) sync. If you really need to get back to a VGA connector, you can use an RGBHV to DE15 adapter, and away you go. You can even use it on other consoles that output 15KHz RGB, but without a separate CSync source.
you can modify a CGA monitor to take analog RGB+H+V at the 15khz (by hacking or modding the tube’s video drive circuit) but if the monitor was designed for exactly 15.0k and you feed it 15.7k then it wont last long and the (resultant / used)voltages may be slightly altered.
Required not requited
Surprising not surprising
No need to open the box. Get a RGB adapter cable for 5€ with that proprietary AV-plug on one end and a SCART plug on the other.
Might try it out, I’m an owner of a Nec 3D which handles 15khz
I still have my playstation 1 with mod chip intstalled. Works great. Also have about 50 games copied on CD’s. Its looking like this playstation is going to out live me. 🙂
Just Buy this cheap adapter and done! HDMI output to any monitor at 1080p http://www.aliexpress.com/item/33050183041.html
THIS ISN’T VGA!!!
I added this VGA port to my fat PS2 long time ago. It was when i figured out that you can alter game files to produce progressive scan. And played games also that had that support already implented. Later the “GSM”-application got released that forced progressive scan for anything.
It was a hardware and software hack that can make it display on VGA screen.
Maybe there is something similar on PS1.