Composite Video

[Eudimorphodon]

I'm on the lookout for an old 4:3 aspect ratio LCD TV.

If the output from the C1P really is this far out of whack then maybe you should consider trying to lay hands on a CRT monitor. (Apple Monitor ///‘s and similar are still… out there.) The scalers in large premium brand TVs are, in my experience, amazing, and completely different animals from what you’ll find in a small TV. If you’re going to try this route look for a good brand, at least. Some knockoff RCA or whatever is very likely to be just as picky as the adapters, if nt worse.

 

[Bruce Tomlin]

From what I understand, those little HDMI scalers are based on LCD panel scaler chips, so they are likely to have similar problems, depending on what chipset they use.

 

[IanB]

I've recently acquired a vintage computer (specifically on Ohio Scientific C1P) that outputs composite video. Has anyone had success with adapters found on Amazon, eBay and other places that purport to convert composite video to VGA or HDMI? If not, what's an inexpensive way to display a composite video signal? I was sorely disappointed when my Dell 2007FP monitor (which has a composite video input) refused to have anything to do the video output from my C1P.

The analog version of the open source RGBtoHDMI project supports the C1P / Superboard and similar mono computers (I'm currently the maintainer of this project):
I have previously used it with a Dell 2007FP although I mainly use HP 1600x1200 monitors

Home

Bare-metal Raspberry Pi project that provides pixel-perfect sampling of Retro Computer RGB/YUV video and conversion to HDMI - hoglet67/RGBtoHDMI

github.com

Here are some screencaps from the output

1080p:


1600x1200:


Also I added an option on the latest release specifically for the superboard to join up the dots:

 

[jim11662418]

The analog version of the open source RGBtoHDMI project supports the C1P / Superboard and similar mono computers (I'm currently the maintainer of this project):
I have previously used it with a Dell 2007FP although I mainly use HP 1600x1200 monitors

Home

Bare-metal Raspberry Pi project that provides pixel-perfect sampling of Retro Computer RGB/YUV video and conversion to HDMI - hoglet67/RGBtoHDMI

github.com

Here are some screencaps from the output

1080p:
View attachment 1259132

1600x1200:
View attachment 1259133

Also I added an option on the latest release specifically for the superboard to join up the dots:
View attachment 1259134

Impressive work!
I have two quick questions:
1. How do I "join up the dots" to make my display look like the third picture above?
2. Do I need to explore all the menu options or will I only be getting myself into trouble?
Thanks.

 

[jim11662418]

Impressive work!
I have two quick questions:
1. How do I "join up the dots" to make my display look like the third picture above?
2. Do I need to explore all the menu options or will I only be getting myself into trouble?
Thanks.

Found the answer to question 1: "YUV Pixel Double".

 

[IanB]

2. Do I need to explore all the menu options or will I only be getting myself into trouble?
Thanks.

Generally the only things you need to do to set up an RGBtoHDMI is use the "Select profile" menu to select the computer you are using and then run an auto calibration using either a long press of SW3 or the main menu option.
After calibration you should press the Menu button to save the new value if the image looks OK so that it uses that on next power up (calibration should be performed with Pixel Double switched off).

In rare circumstances you might have to adjust the DAC levels in the sampling menu to get a stable noise free image if the computer video levels are higher or lower than expected.
Other than that you can play around with the preferences to select things like scanlines or the palette menu to change brightness and contrast etc although there isn't much point doing that with a monochrome image.

The other menus are generally concerned with setting up profiles in the first place so you won't need to tweak those other than the above mentioned circumstances unless you want to add a profile for a new computer.

Most of the options are covered in the wiki:

Reference Guide

Bare-metal Raspberry Pi project that provides pixel-perfect sampling of Retro Computer RGB/YUV video and conversion to HDMI - hoglet67/RGBtoHDMI

github.com

Although it is a little out of date as I need to update it for some recent additions like the "Select Profile" menu and "YUV Pixel Double"

 

[Reaperducer]

Its true. but if a 1977 Atari VCS can work on a modern composite input I figure most things from then and going forward will. Prior to that,, who knows.

The Atari VCS doesn't output composite. It outputs RF.

It can be modified to add composite output, but that requires adding a bunch of circuitry to the machine.

 

[VERAULT]

The Atari VCS doesn't output composite. It outputs RF.

It can be modified to add composite output, but that requires adding a bunch of circuitry to the machine.

Your taking what I said out of context. We all know know what the VCS is and does. I was referring to a composite mod. And that statement is moot at this point.

The point I was making was plenty of used modern-ish flat panels have Composite inputs.. we were not discussing Atari VCS.