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Recording CGA / Monochrome graphics to YouTube?


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Hey guys, I'd like to go through all my old CGA / Monochrome games, and I was wondering how I would go about recording them to YouTube. Is there a device that I can install "in-line" of my Monochrome monitor that will allow me to record this feed?

 

 

Thanks!

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CGA monochrome video is normally compatible with standard composite video, so you should be able to tap it with any recording video card, even USB sticks ones.

 

 

Hmm... ok. It's a 9-pin connector, not the composite. Does that just mean that I need to pull some of the leads off?

 

It's currently set in monochrome format right now (black and green). I wonder if there's any way for me to keep it in that format... doubt it since I assume the feed has nothing to do with the fact that the monitor is green...

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I'm not sure if a monochrome/color in one graphic card does exist.

 

Color graphic card has a composite video.

 

Monochrome card has a print port.

 

You should give us more information about the computer you want to play color/mono games.

 

A VGA computer would play these games but it might don't have a composite video.

 

You will need a special adapter to play on television.

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I'm not sure if a monochrome/color in one graphic card does exist.

 

Color graphic card has a composite video.

 

Monochrome card has a print port.

 

You should give us more information about the computer you want to play color/mono games.

 

A VGA computer would play these games but it might don't have a composite video.

 

You will need a special adapter to play on television.

 

 

Well, it's basically a KayPro 8088 computer with DOS 5.0. I was hoping to record some of the old, old, DOS games (like 1985 and older) as I remember them from the 80s, and record them on YouTube. Things like REDBARON.EXE, GRIME.EXE and stuff like that...

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https://en.wikipedia.org/wiki/Color_Graphics_Adapter#Connector

 

If your video card doesn't feature a RCA conenctor for composite (or a RF out), you'll need to make an adapter cable.

 

The pins you're gonna need there are pin 1 or 2, 6, 8 and 9.

1/2 are ground, 6 is intensity, it should deliver the black and white signal.

You need then to tie pins 8 and 9 together to get a sync signal, this is usually done with a LM1881 chip that take H and V signals and properly convert them into standard NTSC sync signal.

You the wire the sync signal and the pin 6 signal to get your video out.

 

As you guessed, the signal will be in black and white. The green color come from your screen.

BTW you might realize that most of your games are in fact in colors if you had a CGA color monitor. But I like the idea of monochrome games so... Just my two cents.

There are ready-made boards that convert CGA to VGA; but you'll need a device to capture VGA video then.

Edited by CatPix
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https://en.wikipedia.org/wiki/Color_Graphics_Adapter#Connector

 

If your video card doesn't feature a RCA conenctor for composite (or a RF out), you'll need to make an adapter cable.

 

The pins you're gonna need there are pin 1 or 2, 6, 8 and 9.

1/2 are ground, 6 is intensity, it should deliver the black and white signal.

You need then to tie pins 8 and 9 together to get a sync signal, this is usually done with a LM1881 chip that take H and V signals and properly convert them into standard NTSC sync signal.

You the wire the sync signal and the pin 6 signal to get your video out.

 

As you guessed, the signal will be in black and white. The green color come from your screen.

BTW you might realize that most of your games are in fact in colors if you had a CGA color monitor. But I like the idea of monochrome games so... Just my two cents.

There are ready-made boards that convert CGA to VGA; but you'll need a device to capture VGA video then.

 

 

That's perfect, exactly what I need. I actually have an RCA to USB converter that will allow me to record anything in digital format that I can pull off the RCA. So that SHOULD work then... if I can make the adaptor cable like you say. Only thing at that point would be to convert the audio from PC speaker to L/R channel sound. Is the output on the PC speaker unpowered (relatively speaking) meaning... if I connected it as an input, would it damage anything?

 

Yeah, I used to play those games in CGA when I had a VGA monitor (I had a Genoa Systems Super VGA 800x600 resolution card, and a Logitech 640x480 VGA monitor). It was in Cyan, Magenta, and Aqua or something... pretty awesome, hahah...

 

 

 

Is this your computer?

 

http://www.old-computers.com/museum/computer.asp?c=1044&st=1

 

 

Which graphic card is installed? (CGA, Hercules, EGA, VGA, ...)

 

 

Yes! Hahah... my original one, which has an EGA / VGA graphics card, is in pieces. The one that I'm using right now is a brand new one with a Hercules / CGA graphics card in it. But I'm not going to modify that one. My original one, which has wear... Is probably the one I'm going to get working so that I can record stuff off of.

 

 

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I think that you can connect your PC speaker to a line input, with only a resistor, but more to avoid saturation of the line input. There isn't any risk of damaging anything, jsut to have poor audio :D

I do'nt remember what resistor values would be safe however.

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So, I've got a decision to make...

 

I have a brand new, never molested, KayPro PC that I bought at auction. The way it is now, is the way it was when it was brand new... all the factory software and everything.

 

I've got a KayPro PC-10 with 4 external drive bays, it's kind of tatty, and although it gives error beeps, it certainly doesn't boot into anything.

 

 

... then I've got my original KayPro PC... which is identical in every way to the new one I just bought... battery acid all over the inside, the computer case is totally shot inside, the boards are trashed too.

 

Do I molest the brand new one and put my good stuff in there (my two Seagate ST-225s and the 3.5" floppy, and then just put all the other stuff up for sale on eBay?

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As long as you don't have to solder stuff or cut into things, I do'nt see why it would be molesting, as revertign the NOS one is simply pulling back cards and added hardware. This is my personnal POV of course, but as long as it's reversible, and if it use hardware from BITD, it's not "molesting"

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aye I agree, as long as there is no modding of the circuitry adding cards and drives is easily reversible, the worst thing one can do is chip the paint with the screw heads, which your going to do anyway to get that damn battery out anyway.

 

right?

 

Right?

 

RIGHT?

 

I would make a backup of everything the way it stands, im kind of a n00b to the CP/m world but if MSD had backup programs stock on version 3 I am sure there's something out there to back crap up to floppy in a archived format

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https://en.wikipedia.org/wiki/Color_Graphics_Adapter#Connector

 

If your video card doesn't feature a RCA conenctor for composite (or a RF out), you'll need to make an adapter cable.

 

The pins you're gonna need there are pin 1 or 2, 6, 8 and 9.

1/2 are ground, 6 is intensity, it should deliver the black and white signal.

You need then to tie pins 8 and 9 together to get a sync signal, this is usually done with a LM1881 chip that take H and V signals and properly convert them into standard NTSC sync signal.

You the wire the sync signal and the pin 6 signal to get your video out.

 

As you guessed, the signal will be in black and white. The green color come from your screen.

BTW you might realize that most of your games are in fact in colors if you had a CGA color monitor. But I like the idea of monochrome games so... Just my two cents.

There are ready-made boards that convert CGA to VGA; but you'll need a device to capture VGA video then.

 

This is wrong, you will almost certainly not get a usable picture from this method. The CGA pixel is made up of four values, Red, Green, Blue and Intensity. This gives you 16 colors, cut away three of those lines and you won't have much signal left.

 

If you want a workable monochrome picture, you will need to mix in the R, G & B pins as well as the I pin in.

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Alright. Most micro-coputers like the Amstrad CPC use only the I pin for monochrome monitors. I assumed it was the same here. Then we should look on how to mix those, as I remember trying this method for the fun of it, and adding them without filtering result in a mostly dark image (especially when the red is threw in.

I have a monochrome VGA monitor and it tap only on the green signal, but VGA doesn't have intensity signal, if I recall correctly.

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I have a couple hours to kill while the baby takes a nap and a cga laptop

 

I was going to convert it from digital to analog rgb and jam it in the VGA port of the TV I use for a retro monitor but I'll try making a summer for grayscale composite real quick

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ok I clobbered together a resistor daq and a sync summer I see a couple problems

 

1) the sync on CGA is positive moving, its negative moving on NTSC

2) when you plug it into a video input your taking a pile of resistors in funny configurations and then adding 75 ohms to ground as a giant voltage divider and the signal is super weak

 

so I dont think its going to be a passive device its going to need (at least) transistors to invert the sync and buffer / amplify the signal. there's no voltage on the cga connector so its going to be another box to plug in

 

I might tinker with it some more, but now I know

 

just for the record here is signal composited, you are seeing multiple lines of video there, but not the whole frame

 

post-35237-0-24559300-1467741426_thumb.jpg

Edited by Osgeld
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Guys, you're not even going to believe what I did... I hesitate to even tell you guys, because I'm embarrassed at my own incompetence.

 

I've hooked up, installed, and configured numerous RLL / MFM drives over the years. My original KayPro, before the battery fried while it was in storage for 2.5 years while I was out for work... had two RLL hard drives. A Seagate ST-225, and an ST-251. They ran awesome, and I had everything on there.

 

On top of that, this new KayPro I had, came with a brand spanking new Seagate ST-225.

 

 

I forgot that they don't have self-parking heads, and that you have to be extremely delicate with them. Well... somehow, I managed to destroy all three drives by removing them and re-installing them. They all have boot sector errors and can't boot. I'm beside myself. I mean... not to be dramatic, no one died... but I kind of feel like I just dropped a vintage bottle of win from Thomas Jefferson's personal vineyards. I basically just destroyed assumingly the last NOS KayPro 8088. All the original software that was on there... gone. I didn't think I was being that rough... I'm usually extremely delicate with this stuff, but I just forgot how much more delicate this old equipment is compared to today's IDE / SATA drives....

 

 

Sigh... please flame me.

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ok I clobbered together a resistor daq and a sync summer I see a couple problems

 

1) the sync on CGA is positive moving, its negative moving on NTSC

2) when you plug it into a video input your taking a pile of resistors in funny configurations and then adding 75 ohms to ground as a giant voltage divider and the signal is super weak

 

so I dont think its going to be a passive device its going to need (at least) transistors to invert the sync and buffer / amplify the signal. there's no voltage on the cga connector so its going to be another box to plug in

 

I might tinker with it some more, but now I know

 

just for the record here is signal composited, you are seeing multiple lines of video there, but not the whole frame

 

attachicon.gifIMG_20160705_124432053.jpg

As I mentionned, you need a LM1881 chip to turn the H and V syncs into composite sync.

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the 1881 is a sync seperator it does just the opposite (turning csync into vsync and csync, I have used them a lot) and has no effect on polarity

 

combining the two signals into a composite sync is a simple matter of diode oring them together (actually Xor would be better) but doesnt change the polarity of the sync, most IBM compatibles uses positive voltage for sync, most TV standards uses 0 volts for sync

 

:P

Edited by Osgeld
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well I started off this morning with genuine interest, and after the exterminators came and I painted another room in the house the engineering of a solution turned out to be eh lets just see if it works

 

best I got with an educated guess , and that's about as far as i am willing to go down this rabbit hole

 

Captured with my tv tuner card, NTSC, with grayscale graphics (which ends up all rainbow thanks to artifacting)

 

post-35237-0-09916300-1467761844_thumb.jpg

 

update I cant help it

 

post-35237-0-94007100-1467762736_thumb.jpg

Edited by Osgeld
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