Retropie 240p 15 KHz RGB SCART TV Guide

[t0nito]

Hi I'd like to contribute with a guide for those interested in using your retropie on a CRT RGB 240p 15 kHz, any questions feel free to ask.

Here's a video demonstrating Retropie running in 240p RGB on a 37cm (14") CRT TV.

My setup:

Raspberry Pi - cheap HDMI to VGA converter - DIY VGA to SCART cable - SCART TV

My video settings are:

hdmi_group=2
hdmi_mode=87
hdmi_cvt=336 249 60 1 0 0 0

or if your TV doesn't support 60Hz, here's 50Hz PAL mode:

hdmi_cvt=320 312 50 1 0 0 0

I came to the conclusion that 249p gives a much closer to spec signal than 262, with 262, raspberry pi outputs a 16.2kHz 59 fps frequency the horizontal frequency is a bit too high and the screen becomes more narrow, at 249 you get 15.6kHz at 59.6 fps which is much closer to spec.

My HDMI to VGA converter is a cheap one you find all over ebay with the analog audio output

I've done a cable using Cat 5e UTP cable a VGA plug, a SCART plug, a audio 3.5mm stereo lead, a USB cable, 2 1k resistors and a 100 Ohm resistor, schematic here (solder side):

I used a USB cable instead of the molex plug (discard the 12V connection, you don't need it)

http://www.geocities.ws/podernixie/htpc/vga2euro.gif

Here is a photo of my home made cable and HDMI to VGA converter:

https://s27.postimg.org/m5a31iiv7/IMG_20170129_193546_1.jpg

Cheap and easy, amazing 240p scanline goodness :D

Here is my config.txt if anyone's interested:

http://s000.tinyupload.com/index.php?file_id=77919772589799662044

Here are my relevant video settings per emulator which looks best for me:

All emulators:
Aspect Ratio Index: Custom
Interger Scale: OFF
HW Bilinear Filtering: ON
All other settings leave as is except the following:

Atari 2600:
Custom Viewport X Pos: 9
Custom Viewport Y Pos: 24
Custom Viewport Width: 320 (1x)
Custom Viewport Height: 210 (1x)

Atari 7800:

CVXP: 9
CVYP: 9
CVW: 320 (1x)
CVH: 240 (1x)

LYNX:

CVXP: 9
CVYP: 27
CVW: 320 (2x)
CVH: 204 (2x)

FBA (Capcom Play System)

CVXP: 9
CVYP: 18
CVW: 310
CVH: 224 (1x)

FDS/NES/SNES:

CVXP: 9
CVYP: 18
CVW: 320
CVH: 224 (1x)

GameGear:

CVXP: 9
CVYP: 14
CVW: 320
CVH: 231

GB/GBC/NP/NPC:

CVXP: 10
CVYP: 15
CVW: 318
CVH: 230

MAME:

Many games have many resolutions so I setup the video temporarily per game

Master System/SG-1000:

CVXP: 9
CVYP: 33
CVW: 320
CVH: 192 (1x)

Mega Drive/32X:

CVXP: 9
CVYP: 17
CVW: 320 (1x)
CVH: 224 (1x)

N64:

I don't use libretto so I can't change the settings but looks good by default

Neo-Geo:

CVXP: 10
CVYP: 18
CVW: 320
CVH: 224 (1x)

Keep in mind that some games are natively 320 or 304 width I keep it at 320 for the most part.

PCE:

CVXP: 8
CVYP: 10
CVW: 320
CVH: 240 (1x)

PSX:

CVXP: 9
CVYP: 10
CVW: 320 (1x)
CVH: 240 (1x)

[DorkVonWaterfall]

why and how do you supply 12v to a USB connector? isn`t USB only 5V?

[t0nito]

Discard the 12V connection, you only need 5V on pin 16 so the TV switches to RGB mode, the 12V on pin 8 is only for the TV to switch to AV automatically.

[GoogleBot]

Good job! Any experience with using the build-in Pi3 AV out? I have some issues with that#

[t0nito]

@GoogleBot Thanks! I didn't explore much of the AV function as even before I purchased the RPi 3 I always wanted to go straight to RGB, the difference is phenomenal.

What I did find out though is that the AV port did not output 240p but 480i, and that was another factor for me to use the HDMI/VGA route. You can buy or build your own RGB to NTSC or PAL transcoder with a few components using a and get composite 240p though.

[pauloasl]

Thanks

[edmaul69]

This post is deleted!

[Melvin.FoX]

t0nito would be grateful for new schematics/diagram for making vga to scart :)
I am at the very beginning of my way to make such connection. I have HDMI to VGA connector but I am curious about combining Hsync and Vsync. Not sure to what kind of CRT you have connected to Pi but I want to find solution for both consumer CRT and Sony BVM.

[Rion]

@melvin-fox Have you looked at

RetroTINK-S, RetroTINK-C and RetroTINK-RGB by @mikechi2

Pi2Scart

Gert's Vga Adapter

Pi2Jamma

[Melvin.FoX]

@rion I haven't asked for adapters but for diagram for the cable he made and that's a different story.

[twd]

@melvin-fox it's just a simple vga to scart wire nothing special ... You can build one yourself just google rgb vga to scart

[Melvin.FoX]

Sure but VGA has Vsync and Hsync separately and CRT TVs (typical ones, not PVMs) uses Csync which is combined. You can't just join those two pins to one sync so my question is about the diagram as there are few but haven't found one that someone built and checked...

[twd]

@melvin-fox but your ouput isn't vga its RGB 15hz vga is just the cable that feeds the signal. Well I combined them on my dreamcast on pi seems to work fine for my crts

[Melvin.FoX]

But it's RGBHV not RGBC :)

[t0nito]

@melvin-fox The diagram is on the original post but I will link it here in case you missed it:
http://www.geocities.ws/podernixie/htpc/vga2euro.gif
Anyway you just don't join the Hsync and Vsync together, you must put a 1k resistor on each line before combining them together.