Console Emulation to a 15KHz horizontal sync CRT

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Joined the "RGB 15KHz native CRT video output emulation" master race, some time ago.

There are a few ways to go about doing this. This is about the route I took, but isn't a how-to.

The entire system consists of: - 15KHz horizontal CRT with 75 ohm RGB inputs - PC with one of a particular range of ATI Radeon video cards that has analog output (VGA or DVI-I) - ATI Radeon HD 6670 - CRT Emudriver 2.0, a patched ATI video driver that enables 15KHz sync output from one of a particular range of models of ATI video cards - Extron RGB 192V, universal computer-video interface. Basically a breakout box for the VGA's 75 ohm, 0-0.7 Vpp RGB and the sync signals, with some additional processing features and a sync combiner.

Obtained a suitable CRT. I don't have a PVM/BVM or a CRT with SCART, so I chose the "hack a TV to accept RGB input" route. PVM/BVM's bigger than around 13" are obscenely expensive, and I'd be hard pressed to find a NTSC TV with SCART. The TV I happened to score is a Samsung 21" with a TDA8373 "jungle chip" for free that was destined for the dump. The particular jungle chip has a set of 75 ohm, 0-0.7 Vpp RGB inputs and a blanking pin, that is used for the on-screen menu display (OSD). That RGB signal it accepts just happens to be the same one output by VGA and the Extron RGB 192. The idea is to inject your own RGB signal into those RGB pins used for the OSD. I wired in some BNC connectors for the RGB inputs to the TV, and using a 4PDT switch I whacked the 3 RGB signals for the OSD on one side and 75-ohm terminated BNC connectors on the other. Output of the switch then soldered to the jungle chip RGB inputs. For the blanking signal, I tied one side of the 4th 4PDT switch terminal to 3V and the other side to the OSD blanking signal to hold it high. The switch switches between OSD mode and RGB input mode. There was enough space on the end of the TV's main board next to it's RCA inputs to install a home-made bracket to hold the BNC connectors, in order to keep the wire lengths as short as possible. I did check the TV schematic to make sure the TV would be happy with the sync signal provided by the Extron, good to go.

A place to get started doing this yourself would be here:

Video card and CRT Emudriver 2.0 Certain ATI video cards are compatible with a patched driver called CRT Emudriver by Calamity that enables 15KHz horizontal sync output on the analog port. The CRT Emudriver package comes with a couple utilities called Video Mode Maker and Arcade OSD. The CRT Emudriver enables 15KHz horizontal output on the video card, the VM Maker allows creation of special video modes for the CRT, and Arcade OSD lets you tweak the video modes.

CRT Emudriver 2.0 download page:

For a smoother installation experience, I recommend getting a ATI Radeon HD 5450 or later model video card. Installation instructions for later models:

Installation instructions for HD 4350 and earlier model video cards:

Documentation for CRT Emudriver, VM Maker, and Arcade OSD:

Hooking PC up to TV The VGA from the PC is connected to the Extron RGB 192's VGA input. The RGB outputs from the Extron are connected to the TV's new RGB inputs. The composite sync output from the Extron is connected to the TV's composite video input with a 75-ohm BNC to RCA cable. Once CRT Emudriver was installed, and the video modes created and enabled with VM Maker, turned on the TV and got excellent picture. Extron RGB 192:

I got my lot of 2 Extron's for damn cheap on Ebay. Didn't come with the power connector, had to order a couple of those from Digikey.

Emulator The documentation describes how to set up MAME. I have not tried that yet. Have been using RetroArch instead. The latest versions of RetroArch now support CRT Switchres and super resoultions right out of the box. A good instructional on setting up RetroArch is located here:

The RGB picture at the emulated console's native resolution is truly something to behold. Worth all of the effort, in my opinion. The kids get a kick out of it too.

I left out the vast multitude of headaches I encountered along the way, post is long enough already. Everyone's experience will likely be different, have a unique set of circumstances, so troubles won't all be the same.

The reason I wrote this up is so that you understand that because of all this I, member of the 15Khz master race, am most certainly better than you if you're still engaging in "profane emulation."

If anyone decides to pursue such a challenge, feel free to PM with questions or whatever. Niggers.

Joined the "RGB 15KHz native CRT video output emulation" master race, some time ago. There are a few ways to go about doing this. This is about the route I took, but isn't a how-to. The entire system consists of: - 15KHz horizontal CRT with 75 ohm RGB inputs - PC with one of a particular range of ATI Radeon video cards that has analog output (VGA or DVI-I) - ATI Radeon HD 6670 - CRT Emudriver 2.0, a patched ATI video driver that enables 15KHz sync output from one of a particular range of models of ATI video cards - Extron RGB 192V, universal computer-video interface. Basically a breakout box for the VGA's 75 ohm, 0-0.7 Vpp RGB and the sync signals, with some additional processing features and a sync combiner. Obtained a suitable CRT. I don't have a PVM/BVM or a CRT with SCART, so I chose the "hack a TV to accept RGB input" route. PVM/BVM's bigger than around 13" are obscenely expensive, and I'd be hard pressed to find a NTSC TV with SCART. The TV I happened to score is a Samsung 21" with a TDA8373 "jungle chip" for free that was destined for the dump. The particular jungle chip has a set of 75 ohm, 0-0.7 Vpp RGB inputs and a blanking pin, that is used for the on-screen menu display (OSD). That RGB signal it accepts just happens to be the same one output by VGA and the Extron RGB 192. The idea is to inject your own RGB signal into those RGB pins used for the OSD. I wired in some BNC connectors for the RGB inputs to the TV, and using a 4PDT switch I whacked the 3 RGB signals for the OSD on one side and 75-ohm terminated BNC connectors on the other. Output of the switch then soldered to the jungle chip RGB inputs. For the blanking signal, I tied one side of the 4th 4PDT switch terminal to 3V and the other side to the OSD blanking signal to hold it high. The switch switches between OSD mode and RGB input mode. There was enough space on the end of the TV's main board next to it's RCA inputs to install a home-made bracket to hold the BNC connectors, in order to keep the wire lengths as short as possible. I did check the TV schematic to make sure the TV would be happy with the sync signal provided by the Extron, good to go. A place to get started doing this yourself would be here: [https://shmups.system11.org/viewtopic.php?t=56155](https://shmups.system11.org/viewtopic.php?t=56155) Video card and CRT Emudriver 2.0 Certain ATI video cards are compatible with a patched driver called CRT Emudriver by Calamity that enables 15KHz horizontal sync output on the analog port. The CRT Emudriver package comes with a couple utilities called Video Mode Maker and Arcade OSD. The CRT Emudriver enables 15KHz horizontal output on the video card, the VM Maker allows creation of special video modes for the CRT, and Arcade OSD lets you tweak the video modes. CRT Emudriver 2.0 download page: [https://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1009#p1009](https://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1009#p1009) For a smoother installation experience, I recommend getting a ATI Radeon HD 5450 or later model video card. Installation instructions for later models: [https://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1052#p1052](https://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1052#p1052) Installation instructions for HD 4350 and earlier model video cards: [https://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1016#p1016](https://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1016#p1016) Documentation for CRT Emudriver, VM Maker, and Arcade OSD: [https://geedorah.com/eiusdemmodi/forum/viewforum.php?id=1](https://geedorah.com/eiusdemmodi/forum/viewforum.php?id=1) Hooking PC up to TV The VGA from the PC is connected to the Extron RGB 192's VGA input. The RGB outputs from the Extron are connected to the TV's new RGB inputs. The composite sync output from the Extron is connected to the TV's composite video input with a 75-ohm BNC to RCA cable. Once CRT Emudriver was installed, and the video modes created and enabled with VM Maker, turned on the TV and got excellent picture. Extron RGB 192: [https://www.extron.com/product/rgb192](https://www.extron.com/product/rgb192) I got my lot of 2 Extron's for damn cheap on Ebay. Didn't come with the power connector, had to order a couple of those from Digikey. Emulator The documentation describes how to set up MAME. I have not tried that yet. Have been using RetroArch instead. The latest versions of RetroArch now support CRT Switchres and super resoultions right out of the box. A good instructional on setting up RetroArch is located here: [https://cdcruze.com/2019/03/retroarch-and-crt-emudriver-setup-guide/](https://cdcruze.com/2019/03/retroarch-and-crt-emudriver-setup-guide/) The RGB picture at the emulated console's native resolution is truly something to behold. Worth all of the effort, in my opinion. The kids get a kick out of it too. I left out the vast multitude of headaches I encountered along the way, post is long enough already. Everyone's experience will likely be different, have a unique set of circumstances, so troubles won't all be the same. The reason I wrote this up is so that you understand that because of all this I, member of the 15Khz master race, am most certainly better than you if you're still engaging in "profane emulation." If anyone decides to pursue such a challenge, feel free to PM with questions or whatever. Niggers.

[–] • 2 pts

I've always wanted to do this, most people use the OSB to inject a RGB signal.

It should be technically possibly to bypass the composite buffer where it takes the composite signal and creates RGB, there has to be a way to inject it there, along with Hs and Vs. Therefore you don't have to flip a switch and be able to use the OSD at the same time.

[–] [deleted] • 0 pt

The jungle chip TDA8373 takes in composite video signal from an analog switch and decodes it internally to produce the RGB.

I think I've seen a schematic where someone made a mixing circuit that mixed the RGB and OSD together, though can't find it now.

Once read an article of someone connecting RGB to the tube neck board. It wasn't trivial or straight-foward, he had a special amplifier circuit. There were many issues he had to overcome. Trouble is, I can't find that one now either!

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