Stargate Acting Very Strange - Numbers are letters!

[BrianDP]

I bought a new arcade game last weekend.   A Stargate machine that appeared to need a little tender loving care.  I plugged and re-plugged all the horrible Skin-your-knuckle plugs.  Why do they make them so hard to get on and off?  And why are they made out of some metal that seems to corrode from looking at it?  Anyway.  Got the game so it would power up.  It reported a RAM error, 1-2-5.  I got some 4116 ICs from Jameco, and fixed that.  The speaker was detached.  I replaced the speaker with one from an old PC.  The up control wasn't working, which turned out to be another corrosion problem with the pins and sockets from corrosionville.

Now, the game starts, and seems to play.  I should note that there are no batteries in the holder FWIW.  So, when you start the game, it says, that it's lost it's mind, and you are supposed to reset everything.  The problems start, when you are supposed to put in the attract message-  Only As and Ss come up.  you can hit fire to enter them.  No matter what though, it ends up with an attract message of "AS   AS   AS   AS." 

More strangeness.  When you get to the bookkeeping totals, they're just wrong.  Gibberish characters in there. Commas, periods, junk.  When it comes to adjustments, it always reads 8000 for a new ship, you can't adjust that at all.  The rest of the numbered settings are unchangeable as well, I recall 41 being the number all of the highs and lows are set to.. Which makes for an interesting play-  It's really hard to play, but it doesn't seem to matter because you have nearly unlimited ships and smartbombs!  If you lay on the inviso though, you can deplete that fairly quickly.  The game never needs credits.  It always has unlimited credits.

On the setup screen, when it comes time to enter your name for the initial high score, it says, "Enter your name (,0) characters"  Surprisingly, it lets you enter your name!  Those characters are right.  I put in there, BRIANDP RIDES AGAIN, but, then it wouldn't ever seem to get to the 'end' and accept the entry.  the cursor continued off the screen.  I had to turn it off and back on to get anywhere.

Finally, during this hard, but not so bad, because you have unlimited ships, I noticed not getting any extra guys-  Until I got to 100,000 points.  I got the "extra man" sound.. Also, Got another one at about 245,000 points as well.  Beats me what is wrong with this thing!  I'm thinking it's head is not screwed on quite right.  Maybe a decoder chip?  Maybe the whole logic board is possessed by the devil, and I'll need to replace it!

Either way though, if I DON'T fix this logic board, and have to get another one outright-  I'll always be able to put this one in for a sort of quasi-Tournament play-  "Play as long as you can stand it!  You'll never run out of men or smart bombs!  You'll just get sick of how hard it is about Wave 16, when they immediately snatch all the humanoids, and them come after you!"

I know I've learned a lot about this game doing this much with fixing it, but I'm COMPLETELY baffled by this.  Any hints anyone?  Possibly Mr. Retroactive can shed some light on this?  I read where you were talking about how these games are more simple than the newer games that have come around.  Does this mean you have a complete understanding of how the game works from start-up?  To moving the little landers around, and the ship scrolling back and fourth as so?  Even with how "simple" computers were back then, it amazes me that they were able to get such a complicated game to work. 

I realize that each type of opponent has it's own behavior, and Landers are simply there to steal humanoids, and baters are there to make sure you don't take too long to kill them, but boy, when you put all these things together, it comes off as a heck of a show!  Like somehow the machine is back behind the scenes pulling the strings going, "Sure, I want to see you drop in on that lander RIGHT before you are going to line up to kill it, I'm going to put one of those mines in your way-  So it seems to blend with the background and you won't be able to see it!"

Thanks in advance for ANY help you can be with this monster in my stargate!

-BrianDP

[RetroACTIVE]

all your book-keeping and attract messages will be garbage unless you replace your batteries.

once you've replaced your batteries... then see what goes... if you still get garbage... we need to check voltage to cmos ram and the ram itself.  I recall it uses a 74LS189 (or 289), which do fail.

you see the cmos ram keeps the book keeping information, like free play, number of creds per coin, extra life reward, high score... all that good stuff... each time you turn on your game, the cmos ram has bogus data.. therefore you it should reset to defaults... however if the cmos device is bad then it won't matter if batteries are installed.

[BrianDP]

Okay.  I put 3 fresh Duracell batteries in place.  Now it remembers it's gibberish when I turn the machine off.    The adjustment screen still is "Stuck" and the first ship says 8100 points, and sure enough, that is when it gave me my first extra ship.  I expected another ship at 16.2, however no go.  I'm not sure what crazy number it gave me another ship at, but it did at least give me a second.

Now for the test readings taken from the plug from the power supply board....

+--------------------------------+
I                                         I
I   I   I   I   I   I   I   I   I   I   I
I   1  2  3  4   5  6  7  8   9  I
I                                         I
<----left most side of the board..

1.
2.
3.
4.
5.  11.32
6. 
7.  4.76
8. 10.89
9. -5.19

I used an exposed screw hole on the board as a ground.

Are there some valid test points ON the logic board so we can see if it's getting good juice to the CPU?

Oh, the characters that it seems to "like" are G and A..  the attract message, no matter what you try to change the characters to, will only change them to GA    GA     GA.   

It also says to enter ",3" characters worth of high score name. and you can't ever enter that many, it's off the screen, so I have to cycle the game again to get it out of setting the high score like that.   On the high score screen, the name "    GA    GA    GA   GA" is retained, and then, all the high scores have the same GA pattern in the 3 letter names for the high scores. 

This game is possessed methinks!

-BrianDP

PS, Mr. Retro,   

[RetroACTIVE]

Those readings look ok... the 5 volts may be a little low... but I'm not sure that is what is going on here...

When you say "adjustment screen" are you referring to the book keeping screen?

I suspect its your cmos ram chip...but...  is the battery holder in good shape? no corrosion?

It could also be the memory protect interlock... the interlock switch on your coin door and coin box actually drive a logic signal that inhibits writes to the cmos ram (chip select).  If the switch is bad (unlikely) or anything along the path to the cmos device's chip select line, it can prevent the microprocessor from writing to the cmos device.

[BrianDP]

It's the "Game Adjustment" screen as referred to in the manual.  You set everything from the number of ships, how many credits for the ships, pricing for left, center and right slots, Free Play..  The manual says after free play, you tell it to go to the next page, however mine continues down the screen with Master Difficulty control, (Initial, Maximum, 1st Wave, Last Wave, Difficulty Acceleration)  Inviso Time per ship Men needed to warp, all the way down to Set Highest Score Name.  None of these settings allow me to change them.  So that would seem to point toward the "memory protect interlock."

Very interesting you should say that, because that seems exactly like what is going on with that - They are in effect, Locked.  I shall trace that circuit, and see if that is open, closed, or what happens with that.  I notice it doesn't seem to matter if the coin door is open or not, it still starts up saying that you have to open the coin door, and restart the unit - again, like it can't tell that it's coin door is open.  And, since that circuit plays that crucial role in locking the memory, Something seems Fubar with that.  Why not just fix it by setting the switch to on, effectively leaving the coin door open all the time?  Is it necessary to open the coin door to perform any of the advance/auto-manual/Hi Score Reset functions?

[RetroACTIVE]

It's the "Game Adjustment" screen as referred to in the manual.  You set everything from the number of ships, how many credits for the ships, pricing for left, center and right slots, Free Play..  The manual says after free play, you tell it to go to the next page, however mine continues down the screen with Master Difficulty control, (Initial, Maximum, 1st Wave, Last Wave, Difficulty Acceleration)  Inviso Time per ship Men needed to warp, all the way down to Set Highest Score Name.  None of these settings allow me to change them.  So that would seem to point toward the "memory protect interlock."

Very interesting you should say that, because that seems exactly like what is going on with that - They are in effect, Locked.  I shall trace that circuit, and see if that is open, closed, or what happens with that.  I notice it doesn't seem to matter if the coin door is open or not, it still starts up saying that you have to open the coin door, and restart the unit - again, like it can't tell that it's coin door is open.  And, since that circuit plays that crucial role in locking the memory, Something seems Fubar with that.  Why not just fix it by setting the switch to on, effectively leaving the coin door open all the time?  Is it necessary to open the coin door to perform any of the advance/auto-manual/Hi Score Reset functions?

when the coin door is closed.. it prevents the book keeping stats from being modified by anything other than the game program (counting credits/updating high score stats etc..)... write access is granted when the door is open so the auto up and advance  / high score reset can function for the operator to actually clear these settings and /or change t hem..

all this points to something either wrong with the cmos ram or chip enable circuit.... I've seen both fail on one board. 

[BrianDP]

Well I won't claim to be a pro at reading wiring diagrams.  For what seems like a simple circuit, "See if the coin door is open" it's awfully hard to track this down!  I see reference to Memory Protect / Interlock Switch a couple of places.

In the documentation (Cabinet Wiring Diagram from the Williams Wiring Diagram for Stargate) I see

8Sw1 "Auto Up"
8Sw2 "Coin Door Advance"

9Sw1 "Cash Box Advance"

6Sw3 not labeled, except as part of the
         "Memory protect Interlock", and apparently
          mounted on the Cabinet

I wonder if Cash Box Advance is not a typo or something.  If 6Sw3 was labeled "Cabnet door," and 9Sw1 was labeled "Cash Box" this might come into focus a little bit more.  I don't understand how Advance and Auto-Up play into this circuit, but that is how it's drawn.  Is the protection just that the advance button is disabled when the door is closed?  That would seem to be rather silly since you can't get to the switch when the door is closed anyway!

Can you give me some test points and I can give you readings?  I've tried both Coin door and cash box switches closed, both open, and what I assume would be the situation for changing the settings, Cash box closed, coin door open, but still won't budge off changing those values.

Also, as it has been from the beginning, when you go to enter the attract message, it only will only display G's A's, sometimes a 0, and sometimes you'll see the <- arrow come up, but in the end, all it accepts as entry is "G A    G A    G A."  This GA GA GA, also seems to override the high score entry, and all of the high score entries down the screen.  I guess we're not at the point of debugging that yet, but I still think there is something deeply wrong with this board-set.



** My machine is missing it's cash box, so I don't exactly know what the cash box has to push the recessed button up in the cash box cabinet.  It must have some stud or something that extends up into that switch area on the front left side of the Cash box so the switch is depressed when the coin box is present.  If I'm wrong about that, someone please let me know.


Thanks again! 

-BrianDP

[BrianDP]

One more thing-  Having the switch in coin box closed, I took the switch out of it's mount, and have it forced closed. 

Once that was accomplished, the other switches ceased to function at all.  No Advance, no high score reset.  When I played the game like that, I noticed it did reset once in the middle of play, but I'm not sure if that was a glitch or something else.  It was the first time it had ever failed in the middle of a game.

-dp

[RetroACTIVE]

One more thing-  Having the switch in coin box closed, I took the switch out of it's mount, and have it forced closed. 

Once that was accomplished, the other switches ceased to function at all.  No Advance, no high score reset.  When I played the game like that, I noticed it did reset once in the middle of play, but I'm not sure if that was a glitch or something else.  It was the first time it had ever failed in the middle of a game.

-dp

If the switch held closed, its a bogus condition... this is a momentary switch. Not surprising that the other switches are blocked.

This is an original williams cab correct?  Because there are two interlock switches 1 for the coin door (mem prot) and 1 for the cash box (advance)... the cash box is the same as the advance button (I beleive) on the coin door.


Last Edit: Corrected description of switch closed, I read your first post wrong...

[RetroACTIVE]

I wonder if Cash Box Advance is not a typo or something.  If 6Sw3 was labeled "Cabnet door," and 9Sw1 was labeled "Cash Box" this might come into focus a little bit more.  I don't understand how Advance and Auto-Up play into this circuit, but that is how it's drawn.  Is the protection just that the advance button is disabled when the door is closed?  That would seem to be rather silly since you can't get to the switch when the door is closed anyway!

Not silly... think about it... when the game is in normal operation... thats when you are updating coin counts and such... when the door is open, the operator is messing around and you don't want to count money at this time.

Can you give me some test points and I can give you readings?  I've tried both Coin door and cash box switches closed, both open, and what I assume would be the situation for changing the settings, Cash box closed, coin door open, but still won't budge off changing those values.

What do you have for test equipment?  Multi-meter, o-scope, logic probe...etc?

Also, as it has been from the beginning, when you go to enter the attract message, it only will only display G's A's, sometimes a 0, and sometimes you'll see the <- arrow come up, but in the end, all it accepts as entry is "G A    G A    G A."  This GA GA GA, also seems to override the high score entry, and all of the high score entries down the screen.  I guess we're not at the point of debugging that yet, but I still think there is something deeply wrong with this board-set.

Nothing "deeply wrong"... user configuration/book-keeping screen problems are VERY common on Williams boards... like I said before... most likely either bad CMOS chip or chip enable logic.

You're board is easily fixable, if you have difficulty or just don't want to bother, I can fix it for you as well.

** My machine is missing it's cash box, so I don't exactly know what the cash box has to push the recessed button up in the cash box cabinet.  It must have some stud or something that extends up into that switch area on the front left side of the Cash box so the switch is depressed when the coin box is present.  If I'm wrong about that, someone please let me know.

Thanks again! 

-BrianDP

You can just leave this switch alone... its for the operator to insert coins without messing up book keeping totals.

Hope this Helps
- Jim

[BrianDP]

I understand now.  It's to keep the counts where they are so if you add credits, the count won't be off from the number of coins in the hopper - assuming you kept that close track.  I'll leave the door switch alone.

Test equipment is a DMM.  If I needed to I could put my hands on an O-scope, althought I haven't the foggiest idea what I'd do with it.  DMM, that's easy-  Two points, here is the numbers. 

If that 74LS189/289 CMOS chip is all you think it'd take, I'd go ahead and order one of those from um.. Well Jameco doesn't seem to carry that.  Kelvin has them, whoever they are-  $3.25 a piece.  Think I should just get one? 

I'm afriad, no matter how much I would like, I'm never going to be very good at fixing electronics.  I was pleased that I got it up and running to this point.  Honestly I'm more interested in just playing the thing after work when I want to let off some steam.  I'm about at the point where I would rather just let a pro fix it.  I just don't want to be seen as giving up.  I give up on too many things in life. 

-BrianDP

[RetroACTIVE]

I understand now.  It's to keep the counts where they are so if you add credits, the count won't be off from the number of coins in the hopper - assuming you kept that close track.  I'll leave the door switch alone.

Test equipment is a DMM.  If I needed to I could put my hands on an O-scope, althought I haven't the foggiest idea what I'd do with it.  DMM, that's easy-  Two points, here is the numbers. 

If that 74LS189/289 CMOS chip is all you think it'd take, I'd go ahead and order one of those from um.. Well Jameco doesn't seem to carry that.  Kelvin has them, whoever they are-  $3.25 a piece.  Think I should just get one? 

I'm afriad, no matter how much I would like, I'm never going to be very good at fixing electronics.  I was pleased that I got it up and running to this point.  Honestly I'm more interested in just playing the thing after work when I want to let off some steam.  I'm about at the point where I would rather just let a pro fix it.  I just don't want to be seen as giving up.  I give up on too many things in life. 

-BrianDP

You certainly could shotgun it... not sure if its just the CMOS device without checking the path to it ... its difficult sometimes determining if logic chips are bad unless you have a multi-channel scope or a logic analyzer where you can examine inputs and outputs simultaneously...  If I didn't have the proper equipment to debug it, for the shotgun approach I would replace all the chip select gates leading to and including the CMOS chip itself.

Like I said... I would be more than happy to fix it for ya... I would not charge you parts unless they were more than 5 bucks... also I won't charge you any labor... this is just fun for me... I enjoy keeping this things alive.  I've already fixed another members stargate as well.  I've got access to very good equipment, so rework will be done with care.  You would only have to pay for shipping both ways.

Give it some thought.

[BrianDP]

Well, you cinched it for me with that.  Funny, I was thinking shotgun as well when I said lets try replacing the CMOS.  But I think I'll just throw it in the mail to ya with return postage, and I'll throw you a few dead presidents along with it.. Let me know what to do. 

In the future I really want to get some Defender boards for it.  How much of the boards have to be swapped to get it to be a defender?  One idea I thought of - and I don't like the idea much - is to just use the CP from it to interface with a MAME Defender/Stargate.  That way, if anything happend to it, *I* could fix it.  Computers are my thing you see.  I'd still rather have the nostalgia of a REAL arcade game - which I've wanted for the last 25 years.

Thanks Jim.

-Brian

How do I feel after "shotgunning" this repair process?   

[RetroACTIVE]

Well, you cinched it for me with that.  Funny, I was thinking shotgun as well when I said lets try replacing the CMOS.  But I think I'll just throw it in the mail to ya with return postage, and I'll throw you a few dead presidents along with it.. Let me know what to do. 

In the future I really want to get some Defender boards for it.  How much of the boards have to be swapped to get it to be a defender?  One idea I thought of - and I don't like the idea much - is to just use the CP from it to interface with a MAME Defender/Stargate.  That way, if anything happend to it, *I* could fix it.  Computers are my thing you see.  I'd still rather have the nostalgia of a REAL arcade game - which I've wanted for the last 25 years.

Thanks Jim.

-Brian

How do I feel after "shotgunning" this repair process?   

Defender and Stargate are not easily changeable... unlike Joust and Robotron....  Defender and Stargate use different CPU and ROM boards.... Robotron and Joust use same CPU and same ROM boards.... Also later model Stargate CPUs are the same ones used by Robotron and Joust too.  For Defender you would need to replace CPU, ROM and reconfigure your sound board too... 

Personally, I'd keep it authentic... its much better... once its working you will have a much better feeling about it... these machines are really quite durable and since its in your home and not in some damp warehouse or pier side arcade, it will last a while    Besides, even though Defender is the first (that makes it a favorite), Stargate is WAY better, in terms of game play and game quality... Defender was rushed... and when they did Stargate they cleaned it up.

PM Sent

[CheffoJeffo]

+fu (yet again) to RetroACTIVE!

 

[RetroACTIVE]

+fu (yet again) to RetroACTIVE!

- keep em coming!

Also... my bad on the ls189... thats not the CMOS, that is the static ram... CMOS ram is 1C - 5114...derrr...  in case anyone was checking my thought process! 

[BrianDP]

Okay.  I can buy that I want to keep it authentic.  The reason I bought the stargate was because I could swap the boards out and make it into a defender, because it has the right button configuration.  My figuring was, that I could make a Stargate into a defender, but not a defender into a stargate!  Well-  Since I never use that stupid Inviso button - I guess I could! 

Listen to me - I haven't even practiced up on stargate yet, and I refuse to use the tools it has!

I guess I was just a purist, and since I flipped my first defender machine over when I was 14, I've always wanted to re-capture that moment in the mall when there was 20 people standing around watching me fly my defender ship.  Of course, now that my bones and muscles have atrophed over time, If I play a stargate or defender for even 10 minutes, my arm feels like it's about to fall off!!    Once I have it up and running, I can build up the fine motor control, and the stamina it takes to beat on the thing for 50 minutes to get to the point of rollover. 

One thing for sure though, my irlfriend is going to be awfully dissapointed when she learns I need to get a second game to make the collection complete!  Defender & Stargate.   

-Brian

[RetroACTIVE]

There is another (possible) option for you...

Depending upon the rev of your cpu board...

If you are able to get your hands on a williams multigame kit... (used to be offered by www.multigame.com) you could get yourself an empty joust/robotron ROM board and reconfigure your system to play Defender and Stargate!...

Here is the catch... Clay Cowgill... the maker of the multigame is out of that busines... so you would have to scour the collector sites looking for a kit that somebody is willing to give up.

Thats what I did so I could play all my williams favorites on one machine... using real williams hardware   http://forum.arcadecontrols.com/index.php?topic=65938.0

[CheffoJeffo]

+fu (yet again) to RetroACTIVE!

- keep em coming!

Ask and ye shall receive -- I've got a problem Joust sound board making its way through the project list ... just gotta finish up this Arkanoid first (and maybe rebuild an MTC9000 -- depends on when the parts come in).

 

[RetroACTIVE]

Ask and ye shall receive -- I've got a problem Joust sound board making its way through the project list ... just gotta finish up this Arkanoid first (and maybe rebuild an MTC9000 -- depends on when the parts come in).

 

Allrighty then! You know where I spend my (ahem free) time 

[RetroACTIVE]

For those that are interested....

Received Brian's CPU board (5770-09656-00 REV B) and the following problems were discovered....

#1  5114 CMOS chip is bad.  It looked like someone previously pulled it from the board... put a socket in the board and then put it back in the socket.... which leads into the next...
#2  Putting that CMOS chip (with cruddy cut too short solder coated pins) into the socket really made a meal out of it... so its connections were not reliable...
#3  The battery connector has seen better days and has been boogered up by someone to make it 'work' since it was a victim of corrosion... its not consistently making contact with the batteries... causing intermittent backup voltage.

Corrective action:

#1 Replace CMOS chip
#2 Replace CMOS chip socket with machine tooled socket
#3 Install lithium battery conversion kit
#4 Replace all electrolytic caps.
#5 Replace 20 Pin IO header with new gold header (not req for this repair but preventative).

These are all common failures of Williams boards.

 

[cw]

well done....another classic williams game alive and kicking!!!!