Getting proper csync from consoles – WORK IN PROGRESS
This page is for advanced users, so I didn’t include diagrams or how-to instructions, just descriptions and links. Please see the main sync page if you need more info on csync.
When finished, this page will show how to get proper 75 ohm sync from each console. I still have a lot of testing to do and will update this page as soon as I have more information. Before starting, please be aware that in the context of retro gaming, there are two types of csync signals: TTL and 75 Ohm. Most displays and processors will require 75 Ohm csync, but some can accept TTL. As a general rule, unless your setup specifically requires otherwise, your target goal is that the cables you use with your consoles will all be outputting a 75 Ohm signal and the target device will also be receiving a 75 Ohm signal. This is important to mention, as some switches and processors actually change the voltage of the sync signal as it’s passed through.
Also, when used in an NTSC setup, composite video and luma are already 75 Ohm signals and don’t require any components on the line when used as sync.
How to check what components are already inside your cable:
Required for each console:
Below, I’ll describe what’s required to get proper 75 Ohm csync from each console and other possible alternatives (if necessary). Under each description, I’ll add a “quick reference” to what components are needed on the csync line (most likely in the SCART head) of each console.
Super Nintendo (NTSC) – All original NTSC SNES’ output TTL sync from pin 3 on the multi-out connector. SNES Mini’s can get TTL sync by connecting pin 18 on the S-RGB chip to pin 3 on the multi-out. All RGB SCART cables that use csync should have a 330-450 ohm resistor on the csync line. Simply adding one to the SCART head is fine.
csync line: 330 ohm, 1/4 watt resistor
Super Nintendo (PAL) – PAL SNES’ have 12v on pin 3 of the mulit-out, NOT csync!!!! If you connect a csync cable to a PAL SNES, yu can damage your equipment!!! I recommend just using a cable that gets sync from luma (pin 7) or composite video (pin 9) on the multi-out connector (luma recommended).
csync line: DON’T USE IT!!!
Sega Genesis 1 / Mega Drive 1 / Master System – These consoles output TTL sync from pin 1 on the A/V connector. All RGB SCART cables that use csync from an SMS should have a 470 ohm resistor and a 10uF – 220uF / 10v (min) – 16v capacitor (with the positive leg facing the console) on the sync line in the SCART head. 10uF is all that’s needed, but it’s very common for people to use 220uF, since many people already have them. Either way, the voltage shouldn’t be below 10v and I prefer 16v to be safe.
csync line: 470 ohm, 1/4 watt resistor and a 220uF/16v capacitor
MK-2000 (Japanese SMS) – The Japanese Master System (often referred to as the MK-2000) does not require any components on the csync line; When connected to a display or processor, it will output around 350mV without anything else needed. In fact, all four lines, RGBs all have the necessary components on the motherboard, so the RGB SCART cable will just be a full passthrough cable – This is the opposite of all other SMS revisions and cables for each consoles are NOT compatible!
Sega Genesis 2, 3 CDX, 32x) – These consoles output TTL sync from pin 5 on the A/V connector. The csync line on these cables should be wired exactly like the Genesis 1 / SMS line explained above.
csync line: 470 ohm, 1/4 watt resistor and a 220uF/16v capacitor
Sega 32x – The Sega 32x jumper cable does not need any components in it. Also, a 5v connection should NEVER be connected between the Genesis and 32x!!! Please read this for more info: http://www.retrorgb.com/32x.html#cablewiring
NES / Famicom – The NESRGB mod offers both TTL and 75 ohm csync output, toggled via jumper J8. If you plan on using a SNES multi-out and standard SNES cable, use TTL to match the SNES’ output. If you’re using a cable with no components in the line, make sure to use 75ohm output.
csync line: Select sync via jumper.
N64 – Only a few revisions of the N64 have csync already run to the multi-out and compatibility isn’t consistent. If csync isn’t required, I recommend using a cable that gets sync from luma (pin 7) or composite video (pin 9) on the multi-out connector (luma recommended). If csync is required, I recommend doing an RGB mod that includes a proper sync signal as part of the mod. At the moment, Voultar’s board is the only one I’m aware of that does this. Performing a mod like this one will allow you to use an NTSC SNES RGB cable that uses csync.
csync line: Either not used, or the same as SNES.
Sega Saturn – You can get csync by using a cable that gets sync from pin 1 on the A/V connector. As far as I know, for all model 1 Saturn’s, all components for the RGB lines are already on the motherboard, however you require a 470 ohm, 1/4 watt resistor and a 100uF, 16v capacitor on the csync line of the cable. More information and pictures are available on the main Saturn page.
csync line: 470 ohm, 1/4 watt resistor and a 220uF/16v capacitor
Sony Playstation – None of the Playstation systems output csync through their A/V ports. Using luma for sync is the next-best option and if csync is required, you can install a sync stripper in the SCART head.
Another solution would be to make your own output port and get csync directly from the Playstation’s video chip. The earlier models use a CXA1645, where you can tap all the RGB signals, plus csync. The later models use a much smaller IC called H7240, or a re-branded version labeled “Sony A2160”. If you have the Sony version, you can tap csync from the via marked in the lower-right picture. If you have the H7240, you’ll have to solder directly to the chip, which is extremely hard and should only be done by people with SMD soldering experience. Unless you plan on adding your own output to the system, it’s easiest to just use a custom cable, getting sync from luma. (Thanks to Oerg866 for the tip and pictures!):
Playstation 2 – None of the Playstation systems output csync from their A/V ports. Using luma for sync is the next-best option and if csync is required, you can install a sync stripper in the SCART head. As an FYI, PS2’s also output all signals via component video and there’s even an option to output 480p via RGsB.
Also, I’ve seen a few guides online that describe how to tap VGA directly from the PS2’s motherboard, but have not gotten them to work. Feel free to contact me if you have more information about this.
Atari Jaguar – All video outputs are available on the back connector, including csync which is pin 5B. Csync requires a 680 ohm, 1/4 watt resistor and a 220uF/16v capacitor on the line.
For more information on the a/v pinout, see the Jaguar section.
Nintendo GameCube – PAL GameCube consoles do not have a csync pin or a luma pin. The only way to get an RGBs signal is to use composite video as sync. If csync is required, you can get an RGB SCART cable with a sync stripper built-in, however keep in mind that a sync stripper in the SCART head will only improve compatibility and not composite video interference.
VOLTAGE WARNING!!! If you use an NTSC SNES “csync” cable on a PAL GC, 12v will be sent down the sync line!!! This will most likely damage SCART equipment it’s plugged into!!!
EVERYTHING BELOW NEEDS TO BE VERIFIED!!! COMING SOON!!!
Sega Dreamcast – I strongly recommend getting a “VGA Box” that will also output RGB (including csync). Check the Dreamcast page for more info: http://www.retrorgb.com/dreamcast.html
Philips CDi – Most front-loading CDi systems use the Sony CXA1145 video chip and can be RGB-modded. I believe the sync output is TTL and requires a 470 ohm, 1/4 watt resistor on the sync line, but I need to verify – It might need a 220uF cap as well.
3DO – All 3DO systems require a pretty complicated RGB mod, which includes a sync stripper. I suggest following the mods exactly as listed, but use a custom connector, to make it easier to get cables for all switches and displays.
Nintendo Wii – Only PAL Wii’s output RGB, however all output component video. In the case of the Wii, I actually suggest using component, as I’ve found very little difference and it supports all resolutions. As an FYI, the Behar Bros makes a great component to VGA / RGB SCART converter called the Garo.
I hope this page had everything you needed, but feel free to contact me if I missed anything. Also, more sync information can be found in the main sync page