- Joined
- Nov 10, 2001
- Posts
- 908
Greetings,
I tried registering on the PC-FX website a few days ago to ask this question more appropriately over there, but it's a pain in the ass and requires "administration approval" which from my experience takes forever and/or never happens.
So screw that. Waste of time.
I will post here instead where I know the far better techs reside anyhow!
Alright, so I recently acquired a Supergrafx and I was getting all excited about playing the 5 (well, seven really) awesome games when my high came crashing down to the floor.
The collector I purchased the system from lives in Belgium and uses a SCART RGB monitor cable connection for his game systems. His Supergrafx console had been internally modified for RGB output via the regular AV din port through the use of a custom scart cable.
1) I already opened the console and verified this. It is mostly how I know this information for that matter. Inside is a small breadboard with a few minor components mounted onto it and wires that tap into the access points on the system for R,G,B. Additional wires then travel from the small board to the din connector and are soldered to the top 3 ***unused"*** pins.
***the original factory din connector is only 5 pins. a common practice in RGB mods to the pcengine-family consoles is to remove and replace the 5 pin din with an 8 pin din, and use the additional top 3 pins for the red, green, and blue connections***
2) Here is where it gets tricky. On the solder side of the main supergrafx board (bottom side) some traces were cut and some jumpers (bridges) were put in place whereby "modifying" what connects to the "other" pins on the din connector.
***i assume that audio left & right were left alone, (there is no headphone port so this would be the ONLY way he could have had sound), but the composite video, may have been cut and replaced with video sync to work with the rgb output***
3) Conclusion...the original din connector has been "modified" and/or "compromised" depending on your point of view, but regardless of that opinion, it no longer (in its current state at least) can be used with the original NEC factory AV cable.
Now, I live here in the USA where sadly, although FAR superior, we do not (never did for that matter) have scart connectors on our televisions. so this mod is nice, and does indeed provide much better resolution to a purist hardcore gamer, but it is worthless to me, at least at this point in time.
So, I figure I have two options. One would be to completely remove the RGB mod inside the console. Repair the cut traces, and restore the original connections to the din connector and in essence put the damn thing "back to normal". Or two, leave it as-is, and do myself (or have done for me if it is too hard or time consuming) an SVideo mod to the supergrafx. HOWEVER, This would still not resolve all of my problems, assuming that the AUDIO portion of the din connector was altered by the RGB mod?
Or is all this too much trouble, and I'd be better off selling this console as an RGB modded console on ebay and simply buying a normal console?
Not to mention how do I even know if the system's scart compatibility is with that of the JAPAN SCART or the EUROPEAN SCART standard?! I have heard that they have different pin outs and are not compatible? Even more headaches!
Long story short, (too late for that), I want to PLAY my damn supergrafx system and I want advice on what would be the best way to try and do that.
***i think for now i will tap into composite video off the expansion bus connector and then plug a custom din connector with ONLY audio left and right connected, plug the 3 RCA cables into my television and say a prayer***
(and then for now i will have some dumb ass ugly wire hanging out the console someplace)
What I REALLY want, is an SVideo mod. But I don't know where to tap into Chroma and Luma?
(or at least a safe and easy way of disabling the RGB internally and restoring the composite)
Any help is appreciated.
Thanks.
By the way, here is the AV pinout of the Supergrafx as it should be from the factory:
http://www.gamesx.com/avpinouts/duoav.htm
UPDATE: Well, I tapped into the composite video at one of the pins on the expansion bus and fished the wire out through the rear of the console (looks super cheesy and ugly) but all for nothing anyhow as the video quality came up absolutely horrible. a blue/red fuzzy out of focus blob with no green or sync. I could see the title and some large objects and such, so at least now I know the console works, but at this point I have to assume that the RGB mod compromised the consoles ability to output in composite video?
I will simply have to look into how the mod was done. More specifically, what did they do to those traces that connect to the bottom 5 pins of the din connector, as well as what other components have been tapped into by the small breadboard used for the RGB amp circuit.
I tried registering on the PC-FX website a few days ago to ask this question more appropriately over there, but it's a pain in the ass and requires "administration approval" which from my experience takes forever and/or never happens.
So screw that. Waste of time.
I will post here instead where I know the far better techs reside anyhow!
Alright, so I recently acquired a Supergrafx and I was getting all excited about playing the 5 (well, seven really) awesome games when my high came crashing down to the floor.
The collector I purchased the system from lives in Belgium and uses a SCART RGB monitor cable connection for his game systems. His Supergrafx console had been internally modified for RGB output via the regular AV din port through the use of a custom scart cable.
1) I already opened the console and verified this. It is mostly how I know this information for that matter. Inside is a small breadboard with a few minor components mounted onto it and wires that tap into the access points on the system for R,G,B. Additional wires then travel from the small board to the din connector and are soldered to the top 3 ***unused"*** pins.
***the original factory din connector is only 5 pins. a common practice in RGB mods to the pcengine-family consoles is to remove and replace the 5 pin din with an 8 pin din, and use the additional top 3 pins for the red, green, and blue connections***
2) Here is where it gets tricky. On the solder side of the main supergrafx board (bottom side) some traces were cut and some jumpers (bridges) were put in place whereby "modifying" what connects to the "other" pins on the din connector.
***i assume that audio left & right were left alone, (there is no headphone port so this would be the ONLY way he could have had sound), but the composite video, may have been cut and replaced with video sync to work with the rgb output***
3) Conclusion...the original din connector has been "modified" and/or "compromised" depending on your point of view, but regardless of that opinion, it no longer (in its current state at least) can be used with the original NEC factory AV cable.
Now, I live here in the USA where sadly, although FAR superior, we do not (never did for that matter) have scart connectors on our televisions. so this mod is nice, and does indeed provide much better resolution to a purist hardcore gamer, but it is worthless to me, at least at this point in time.
So, I figure I have two options. One would be to completely remove the RGB mod inside the console. Repair the cut traces, and restore the original connections to the din connector and in essence put the damn thing "back to normal". Or two, leave it as-is, and do myself (or have done for me if it is too hard or time consuming) an SVideo mod to the supergrafx. HOWEVER, This would still not resolve all of my problems, assuming that the AUDIO portion of the din connector was altered by the RGB mod?
Or is all this too much trouble, and I'd be better off selling this console as an RGB modded console on ebay and simply buying a normal console?
Not to mention how do I even know if the system's scart compatibility is with that of the JAPAN SCART or the EUROPEAN SCART standard?! I have heard that they have different pin outs and are not compatible? Even more headaches!
Long story short, (too late for that), I want to PLAY my damn supergrafx system and I want advice on what would be the best way to try and do that.
***i think for now i will tap into composite video off the expansion bus connector and then plug a custom din connector with ONLY audio left and right connected, plug the 3 RCA cables into my television and say a prayer***
(and then for now i will have some dumb ass ugly wire hanging out the console someplace)
What I REALLY want, is an SVideo mod. But I don't know where to tap into Chroma and Luma?
(or at least a safe and easy way of disabling the RGB internally and restoring the composite)
Any help is appreciated.
Thanks.
By the way, here is the AV pinout of the Supergrafx as it should be from the factory:
http://www.gamesx.com/avpinouts/duoav.htm
UPDATE: Well, I tapped into the composite video at one of the pins on the expansion bus and fished the wire out through the rear of the console (looks super cheesy and ugly) but all for nothing anyhow as the video quality came up absolutely horrible. a blue/red fuzzy out of focus blob with no green or sync. I could see the title and some large objects and such, so at least now I know the console works, but at this point I have to assume that the RGB mod compromised the consoles ability to output in composite video?
I will simply have to look into how the mod was done. More specifically, what did they do to those traces that connect to the bottom 5 pins of the din connector, as well as what other components have been tapped into by the small breadboard used for the RGB amp circuit.
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