Game King with Scrambled Screen

[diamonddot]

I have a game king with a scrambled screen.  It looks like a computer Rug Pattern.  With no visable characters.  I tried to key chip it and no differance in screen.  All yellow lights on cpu are lit and red led flickers on and off.  battery voltage at 2.8 volts.  Any ideas?

[Yoeddy1]

Is that emoticon on your GK screen or do we have a spambot out here infecting the boards?

Jason

[cruisepl]

I have a game king with a scrambled screen.  It looks like a computer Rug Pattern.  With no visable characters.  I tried to key chip it and no differance in screen.  All yellow lights on cpu are lit and red led flickers on and off.  battery voltage at 2.8 volts.  Any ideas?

I dont have a game king but on an IGames the screen you are describing comes from putting a chip in backwards  Pull all the chips and make sure all the notches line up correctly

[diamonddot]

Thanks the only chip I took out was the base chip but someone brought it to me so maybe they were screwing around?  I will check out the chips.

[diamonddot]

OK everything seems fine what about the small 8 pin ic on the back plane board.  I know they get screwed up on S+ slots?  Just a thought

[Bettor Slots]

A reversed or bad Base chip will typically result in a dead screen, blank or black along with a red light on the board.

A scrambled screen (looks like colored confetti) like you are describing is typically the result of one of two things.  One, the Game 1, Game 2, PXL 1, or PXL 2 is not installed properly, reversed, has a single pin sticking out that you are missing, or two...unfortunately, the main board has issues.

[Bettor Slots]

Also, the voltage on your battery is too low.  2.9v is the cutoff, I would suggest replacing it.

[diamonddot]

Heck I'll change battery that is simple.  I'll let you know thanks. 

[Bettor Slots]

Do you have another set of known working software, perhaps a different game title?  This would be a good way to troubleshoot whether the issue is you software or the board that is giving you problems.  If not I am happy to mail you a set on loan if you cover the shipping.

[diamonddot]

Thanks for the offer.  First thing I am going to do it change battery and then try to get the board over to a friends house to give it a try.  i will keep you updated. Diamonddot

[knagl]

I am happy to mail you a set on loan if you cover the shipping.

It's stuff like this (and people like Jim) who make this the best site for home owners of slot machines, hands down.  K+ to you, Jim, for making such a nice offer.   

[Billythekid]

I've got a gameking with the same yellow confetti screen. Here's the bazaar part:

Upon first start up LED's on gameboard were as follows: R1 (flicker) R2 (Solid) G1 (Solid) G2 (Solid) Y1 (off) Y2 (off)

No bill verifier initialization. Confetti screen.

Checked all chip orientation and pins and they were good. Back plane pins all ok too.

--------

I first inserted a new gameboard, key 22'd it (clear screen came up good), and put the original game chips in the new gameboard.

LED Status: R1 (flicker) R2 (OFF) G1 (Solid) G2 (Solid) Y1 (off) Y2 (off)

Bill verifier cycled

Confetti screen returned.

------------

Next I Key 22 clear ram and E2, then inserted a different set of game chips.

LED Status: R1 (flicker) R2 (OFF) G1 (Solid) G2 (Solid) Y1 (off) Y2 (off)

Same confetti screen

-------------

Next I inserted the original game chips into the original gameboard. At first attempt to clear ram and E2 screen came up solid RED. Powered down and repowered up with Key 22 inserted and clear screen came up. Cleared ram and E2, inserted base chip.

This part is new: LED R1 (Flicker) R2 (ON or 5 seconds then off) G1 (on) G2 (on) Y1 (off) Y2 (off)

No bill verifier cycle.

Confetti screen.

After about 45 seconds R2 came on solid.


Keep in mind the second game board first tested in step 1 never displayed R2 on at any point and cycled bill verifier.

-----------------------------

On the motherboard backplane there is a single red LED and this led is always off.


Any ideas?

Thank you!

[OhioGaming]

Since you are using the same chips on both boards it is possible that one the chips are bad.

[Billythekid]

Since you are using the same chips on both boards it is possible that one the chips are bad.

What's getting me is that I have a second set of Game chips that worked, on a board known to work. Niether board nor set of game chips is working in this machine.

The only thing left that I haven't changed is that little chip on the motherboard. Anybody know if a normal condition is for that single red LED on the motherboard to be lit or not?

[Tilt]

Have you checked the power supply output voltages?  The motherboard LED is normally off.

[Billythekid]

Just got done putting a new battery... no go.  On the powersupply no I haven't. Can anyone point me to a schematic of the pin outs and voltage at the pins.

Thanks.

[Tilt]

Can you post a picture of the interior of your machine?   That will help in determining the right schematic for the motherboard.

[aklarry]

I have seen the confetti when I bent a pin on the base chip also installed a base chip that later checked bad and got the confetti
AkLarry

[Billythekid]

It's a 13" 3902. Let me know if this info is enough to know the type. I can go look for specifics on the machine or take a pic of the power supply itself.

[Tilt]

Here's a schematic of the motherboard.  The power supply input is on J11.  Power up the machine without the monitor installed to check it.

[Billythekid]

Little delay on this, I sent both my game boards and game chip sets to be tested in another gameking. They both work. Upon getting them back they do not work in my cabinet. I could not access the schematic you uploaded, said database busy, but if you can msg me with it or email I'll test power supply at J11. Curious why the test is with the monitor out?

Thank you.

[reho33]

If you shake the game from side to side, the pixels will fall into place LOL. (Just kidding)

[Tilt]

Little delay on this, I sent both my game boards and game chip sets to be tested in another gameking. They both work. Upon getting them back they do not work in my cabinet. I could not access the schematic you uploaded, said database busy, but if you can msg me with it or email I'll test power supply at J11. Curious why the test is with the monitor out?

Thank you.

J11 is on the motherboard behind the monitor. It's much easier to get to with it out of the way and you don't have to worry about getting shocked by it either. 

Your email address is hidden in your profile.  PM it to me and I'll email it to you. 

[Inieas]

Just from my experience of the last few weeks, I had the scrambled screen come up from 1. Bad Base Prom. 2. Bad I960 CPU 3. Bad Graphics CPU (Cannot remember that one so much) and also last but not least PXL Roms.

As for the LED Problem, I have had this before and if the LED's you mentioned are dead, it means your board is not getting the 5, 12 or 24V signal. It could be thhe Board itself, the Motherboard or the Power Supply. I have had the Powersupplies giving me problems before and replaced a few of the switching Transister andPower Transisters.

More than this I do not know and hope it helps.

[Billythekid]

UPDATE:

I acquired a new power supply after getting under voltage on both the 24V and 13V. Readings were 20V and 10V. 


I installed new supply and the game loaded and worked!!!! So that under voltage was allowing the Clear chip to run fine but the game chips needed more voltage.

Here's the BAD NEWS. After running machine for about 30 minutes I shut it off and went to bed. Today I turned it back on and CONFETTI SCREEN again.  

I pulled out new power supply and it smells burnt. I measured voltage on it and it's now the same as the old 20V and 10V. 

Super bummed that there must be a shorted wire or component in the system that is putting massive draw on the power supply and permanently damaging it.

At this point the task of finding the culprit is discouraging. Maybe I should sell this machine for parts and start over.