Very strange pin2dmd XL issue (Baywatch)

[Crrispy]

Hello,

 

I have a really strange issue with my pin2dmd XL in my Baywatch. Some colors, not all, are flickering badly, like some shades of grey and blue, but some other colors (most of them) are perfectly stable.

- I swapped the dmd data cable with another one -> same result

- I tried an external power supply instead of the pinball's 18V -> same result

- I then suspected the pin2dmd itself. I just installed a new one, and unfortunately, issue is still there with the brand new one😐So it's not the display for sure.

 

So I could suspect the controller board. But if I remove the sd card and run the pin2dmd with basic/non colored 4 colors palette, all colors are perfectly stable without any flickering, which seems to indicate that the controller board has no issue.

 

A this point I'm quite clueless. Could this be a software/colorization issue?  Firmware is now 4.50, no change.

 

Thanks.

 

 

[lucky1]

Maybe this helps 

https://vpuniverse.com/forums/topic/5975-baywatch-shifting-image-on-display/#comment-57036

[Crrispy]

Hello,

 

Thanks, looks interesting. So in the end it <might> be an issue on the controller board, even if there is no issue without colorization. I have to borrow another controller card to test, I see no other choice atm.  Meanwhile, I will try a couple of other sd cards even if I can't understand the link between the card and this kind of issue. It's not the exact same issue I have btw, no shifting, only flickering of some colors.

 

[lucky1]

Maybe a video of the issue would help

[Crrispy]

It's quite difficult to film, because the pwm of the leds already causes some "waves" on the video, even in the good areas, but here is a short one where the bad flickering is clearly visible on the grey color all around the frame. Here, the Credits display and Push Start text are perfectly stable.

 

It is really on some colors only, for example on the scrolling credits scene which is all in different shades of blue only, only one shade of blue flickers, the others are rock solid.

 

 

[lucky1]

As you can see in the picture the issue is in the rows. White draws the most current !

Did you try a external power supply or lowering the brightness ?

 

[Crrispy]

Thanks for the tips, it works now and it was... the brightness!  I had already tried an external ps, I tried again, result was the same. I then lowered the brightness as you suggested (I had set it high, around 90%, because I installed a polarizing filter in front of the display, which reduces brightness) and problem gone. 

 

What's strange is that it's really on/off. I tried to increase brightness notch per notch, at some point it is perfect, then at the next one it goes real bad like on the video. So I am now on the last good one and it's fine like that. Seems the led drivers are not powerful enough for full brightness of these panels. But the fact that it affects only certain colors, not only the brightest ones, that red & green are unaffected etc... is still a mystery. Red is supposed to need more current than blue for the same brightness seen by the human eye, but in the end it seems the limit is on the blue channel.