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MK4Arcade

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Hello guys,

So I managed to get my mk4 running and I have ran into another problem. I am using the OSSC and the display is very dark. When the rom check screen appears it does so in a dim way. After the rom check everything just turns black, you can see some text but hard to see. Any ideas of what the problem may be?

Thank you
 

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Check the cable running into your OSSC, it likely contains caps and resistors that are knocking the signal down too low.
Describe the video portion (including cables used) of your setup/supergun and I can make some suggestions.

<soapbox> Remember this is why people like me HATE the 9pin mini din connector, its so commonly used for Genesis 2 that to find a straight 9pin din to SCART cable (aka without caps and resistors) is near impossible (you pretty much need to make it from scratch OR modify/remove these components yourself).

In my very binary world using ANY (yes even one single cap/resistor) components inside a cable is WRONG!
Nintendo taught us all this lesion 20 years ago with a little purple PoS they called Gamecube. </soapbox> :P
 
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Let me attach pictures of my setup. FYI I can run mk1 and MK3 with this setup. The scart cable is RGB compatible. I've already played with the settings on my monitor and nothing helps.
 

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Huh, that is a stumper because you have a SCART to SCART cable...
AND you say MK1 and MK3 are both fine too? Yea not really what I was expecting here.
Perhaps the issue is isolated to the PCB its self and not related to the supergun or OSSC at all.

I've never personally owned a MK4 board, is this a common/known issue with them?

I suppose you could crank up the OSSC's amplification settings in a pinch.
I believe it maxes out at 255 (each channel R/G/B and total brightness) so it should get pretty bright I guess. "max ALL the things" *shrug*
 
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Huh, that is a stumper because you have a SCART to SCART cable...
AND you say MK1 and MK3 are both fine too? Yea not really what I was expecting here.
Perhaps the issue is isolated to the PCB its self and not related to the supergun or OSSC at all.

I've never personally owned a MK4 board, is this a common/known issue with them?

I suppose you could crank up the OSSC's amplification settings in a pinch.
I believe it maxes out at 255 (each channel R/G/B and total brightness) so it should get pretty bright I guess. "max ALL the things" *shrug*
Yeah that's what I was thinking too. And yes the other mk's work no problem. I'm not too sure if it's a common problem with them, but based on the videos I've watched mk4 always has some sort of display difference than the rest. I will try that! Thank you! You are always a big help.
 
@jassin000 maxing everything out actually worked! I am having problems with the game being too bright...I adjusted my brightness settings on my TV and you can see from the pictures it didn't help. Any other change that I can make with the OSSC?
 

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Yep, mine does the same thing. The only thing that I did though is just connected the RGBs to the vga input instead of the Scart input and a lot of messing around in the settings to get it looking right. Man! When the settings are correct, the game looks gorgeous. Make sure to save your profile as well.
 
Yep, mine does the same thing. The only thing that I did though is just connected the RGBs to the vga input instead of the Scart input and a lot of messing around in the settings to get it looking right. Man! When the settings are correct, the game looks gorgeous. Make sure to save your profile as well.
Do you think you can share your settings? And yes MK4 looks awesome, just need to figure out this video issue to enjoy it.
 
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Thank you!! I would appreciate it.
I got a question for you, do you know anything about mk4 boards? My board has an issue that I’m hoping to fix and I haven’t found no answers, not even from YourMKArcadeSource.
 
I

I got a question for you, do you know anything about mk4 boards? My board has an issue that I’m hoping to fix and I haven’t found no answers, not even from YourMKArcadeSource.
I actually don't, just barely wanting to get into repairing boards. Yeah that's who I usually watch myself. What's the problem you're having?
 
I actually don't, just barely wanting to get into repairing boards. Yeah that's who I usually watch myself. What's the problem you're having?
The test menu freezes up when I try to get access. I have a video on what it’s doing and also, it doesn’t read all the ram and rom chips at the check up screen. Otherwise, the game plays perfectly fine. Video:
View: https://youtu.be/j28xPiiWSvE
 
@Franco23444 you should probably start your own thread but what happens when you flip on test mode from boot? Dip bank 2 switch 8 ON.
 
@Franco23444 you should probably start your own thread but what happens when you flip on test mode from boot? Dip bank 2 switch 8 ON.
It does the same thing. It freezes up and I have to reset the game in order for it to boot. I’ll make a different thread because this is something people haven’t seen or heard of this issue before and I would like to get it fixed.
 
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Just an update on this. I have finally figured out my video problem. I took off the zero ohm resistors from the RGB on the PCB board and in place put resistors with 330 ohms. I also decided to plug my MK4 directly into the supergun since my JAMMA harness was giving me some audio issues. I'm very happy with the results.
 

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I have an ossc setup too, and I have noticed that MK2/MK3/UMK3 all share the same 'dimmed' look using default settings. MK1 is fine tho.
 
I have an ossc setup too, and I have noticed that MK2/MK3/UMK3 all share the same 'dimmed' look using default settings. MK1 is fine tho.
You should try and mess with the color brightness and contrast in the OSSC. From my experience the JAMMA extension can make a big difference...my first one was cheap and it gave me a couple of problems, picture being one of them. Lesson learned on that one lol.
 
I have an ossc setup too, and I have noticed that MK2/MK3/UMK3 all share the same 'dimmed' look using default settings. MK1 is fine tho.
Did you ever fix this issue? I’m currently having this issue with my board. No solution I’ve tried has fixed the dim look on the board. I don’t own an ossc, but I’ve been trying to run this on an arcade1up I converted. I’m using a gonbes 8200 outputting to vga and tried 3 different vga monitors and the same dim look.
 
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