aristocrat igt 5 reel problem. Play credits switch not working

[bob in phx]

I first off I am new to this forum, but not necessarily new to slots. I currently own a bally 873 5 line em and a bally system 5000, plus a couple of pinball machines. I am not new to circuit board repair and problem diagnosis, but I am new to the Aristocrat IGT!!!!!!!!!!

A family friend bought this machine for cheap, not working. They dropped it off and asked me to fix it. My payment will be a home cooked meal and a beer!!!

Initially the machine would not start at all, only the attract mode sounds would play.
Inspection found that the cpu has come loose from the backplane card and that the CPU had suffered battery damage. The damage was neutrilized with vinegar, baking soda and water. All damaged traces were restored and all electrolytic caps on the cpu were replaced.
All contacts and reel opto's were cleaned.
the machine now works great, with the exception of the large red button/bar above the belly glass that allows you to play your credits. I buzzed out the wiring and it appears to be fine, all the way back to PA0 on 6821 on the I/O card. I swapped out a known good working 6821 and still have the same issue.
so what the heck could be causing my lack of play credit button.
a couple of my thoughts.
1. Wrong game eproms??? but all other functions work fine.
2. socket issues with the 6821, including maybe even the data bus or select lines??, maybe even on one or more of the other 5 6821'a.
3. I am completly nuts for working on this machine for only a dinner and a beer!!!

If anyone has a schematic and or manual (and I have searched the download area of this site), or suggestions, please post!!!!!

thanks in advance!!!

bob in phx

[bob in phx]

update.
I pulled the "new" 6821 and upon close inspection found a lot of gunk in the socket. I then pulled all the other sockets and found that they too were gunked up with a white substance. I added a second new 6821 after really cleaning up the sockets and now, I have a credit buton that works without me touching it!!!!!!!!!!!!!!! so I am afraid that I will be pulling all 5 6821 sockets and replacing them. I sure dont like working without schematics!!!!!

I sure hope that the 7800 series logics and the resistor networks are ok,,, other wise, I see a lot of sockets in my future!!!!!!!!

bob in phx.

[TZtech]

Hi

Do you have a model number and can you post some pics?

[bob in phx]

the model number is rl50a

pics in a moment

[bob in phx]

another of the reels and the power board and meters

[TZtech]

Hello Bob

Thanks for the pics - I am not familiar with this model but i am sure someone else here may be able to assist.
Have a look at this thread http://newlifegames.net/nlg/index.php?topic=527.0 - Looks similar to your machines apart from the number of reels.

Ian

[bob in phx]

Thanks for the update!!! I had looked at that thread and yes, its the same machine.

Having now explored the machine a little, it a very simple design. Everything is 24volts ac and controled by the PIA's/cpu via triacts.

[Op-Bell]

I have one of these, with different glass but otherwise the same except it doesn't have the "play credits" button, and the cash-out button at top left is wired closed, so it always dumps its credits in coin. When I was going through the ROM code I found a place where it looks for the "play credit" switch, so I knew there had to be one. But I don't understand it. From the code, it looks like there are separate buttons for the three lines and you can - no, you have to - select them individually. Can you tell me how the button works on your game? One press plays 3 credits, or successive presses play one credit each? In the middle of the door, just under the window, is a 12 position Molex connector with 4 wires in it, one of which is ground. I believe this connects to the "play credit" switch. So is it three switches, or one switch with three wires (plus ground) attached, or if just one wire + ground, which one? Sorry to ask so many questions.

I have a PDF of the manual for these machines but it doesn't go into exquisite detail. I have also disassembled and commented the ROMs, which may be of interest if you understand 6800 assembly language.

[bob in phx]

The button on this machine is only one button. The molex your talking about, on my machine, only has 2 wires. One from the 6821 (pao) brown with black and a white with green system ground wire. The button is a long bar, with 2 switches, wired in series, at each end of the switch. Now it is very interesting that I found 2 cut wires in the door harness that I can not find mates for!!!! I am now beging to wonder if these are the switch wires.... My thought is that maybe the switch on my machine is wired wrong and maybe its trying to add the 2nd or 3rd line and the cpu is still waiting for the first line!!!! I would really love the code. I am not familiar with the 6800 code, but jcl, fortran and cobal were in my past... point me to a decomplier and I will give it a shot!!!!!!

what colors do you have on the 12 position molex??????

bob in phx.

[Op-Bell]

what colors do you have on the 12 position molex??????

Let me try this table thingie...

^     ^     ^

X     X   WT/GN

RD/GY  X      X

X   BK/GY YL/BK

X      X      X

Hmm, about as good as just typing - I was hoping for a frame. Anyway, view from the back, points up.

This connector is not listed in the wiring diagram, but another one (S15, 9 way) is that carries these yellow/black. red/gray and black/gray wires. S15 and these wires appear in another diagram where they are identified as "spare sw 1", "spare sw 2", "spare sw 3" respectively in one place and "1st line sw", "2nd line sw", "3rd line sw" in another. They trace back to the logic boards in the right place to work with this code: <danger, assembly language ahead>

Code:

; loop back from B0F0
cB06Dc: LDAA    PIA_5A                  ; may be "play credit" switch
                                        ; or 1 line, 2 line, 3 line
        LSRA                            ; bit 1 to bit 0        
        COMA                            ; invert
        STAA    temp_54                 ; save
        BITB    temp_54                 ; 'B' bit check
; As B shifts, will successively test P5A bits 1, 2, 3
        BNE     cB0A7c                  ; P5A bit is low
        TST     play_coin               ; FF if a coin was played
        BEQ     cB0EBc
        LDAA    R3094                   ; cleared at game end
        BITA    #$1                     ; 1 bit per credit played
        BNE     cB08Ac
        LDAB    #$1
        BRA     cB098c
cB08Ac: BITA    #$2
        BNE     cB092c
        LDAB    #$2
        BRA     cB098c
cB092c: BITA    #$4
        BNE     cB0EBc                  ; 3 credits played
        LDAB    #$4
cB098c: PSHB                            ; B has 1, 2 or 4        
        LDAB    PIA_6B
        ANDB    #$FD                    ; bit 1 low
        STAB    PIA_6B                  ; coin accepted
        INC     accept_flag
        PULB      
        BRA     cB0B1c

; one or more lines lit - B has most significant (2,1,0)
cB0A7c: BITB    R3094                   ; already done this line?
        BNE     cB0EBc                  ; yes, pass over
        LDX     cred_bcd
        BEQ     cB0EBc                  ; no credit, pass over

; play 1 credit to game
; B contains a value on entry
cB0B1c: LDX     #cred_bcd
        SEI                             ; disable ints
        JSR     dec_bcd                 ; subtract 1 from credit, BCD
        CLI                             ; enable ints
        LDAA    #$1
        LDX     #lines_bcd
        JSR     inc_bcd                 ; add 1 to lines_bet, BCD
        STAB    temp_54
        LDAA    R3094
        ORAA    temp_54                 ; add bit from B
        STAA    R3094
        STAA    line_lamp_ena
        CLR     play_coin
        LDX     #disp_list
        JSR     decode_displays

        LDX     #cA86Ac                 ; constant A3, 163
        JSR     cB943c                  ; sound
        TST     main_door
        BNE     cB0EBc                  ; door open
        LDX     in_meter                ; play credit meter
        INX        
        STX     in_meter

cB0EBc: ASLB                            ; shift B left        
        CMPB    #$8                     ; bit 3?
        BEQ     cB0F3c                  ; yes, max bet
        JMP     cB06Dc

; max bet reached or tried 3 bits

<edited to tidy up the code block>

[bob in phx]

Well, the cut wires appear to be a rewire of the door harness. The cut wires have been replaced and feed to the right side festoon lights that flash the game instructions, so these wires are a red herring!!!!!. I think I found the secondary connector that you suggested would be "s15, 9 way" the colors you call out are all there and not continued on the other side of the plug, heading to the door!!!.... so, if I understand the way this works, the other two wires (rd/gy and y/blk) should have 5 volts on them if I check with an ohm meter and if they are grounded, this would signal the CPU via the PIA to run the snippet of code you provided!!!! I am off to check the 5volt status of these wires, both when the machine has credits and when it does not.

If I find 5 volts, I am temped to ground them and see if a credit decrements!!! Now if I just knew what color special sw #1 was!!!!!!!!!!!!!

bob in phx...

[bob in phx]

success!!!!!!!!!!!!!!!!!!!!!!!!!!

just inside the door, on the left side cabinet wall, I found the correct color wires. I quicky extended them out to the front of the machine. I measured both the yellow and black, as well as the red and gray. Each measured 4.41 volts. LOGIC LEVELS!!!! I conneted the yellow and black to a push switch and connected the other end to the white and green wire. I put 6 credits up, via wins, with the door closed. I pushed the switch and the number of credits went down by one and the handle lock opened. I spun the reels and won 2 coins, which went to the credits display!!!! Next I tried the red and gray wires, same result. but neither of these wires would add a second credit. very interesting.... So, once I find the proper male molex plugs, I will wire up all three special switches and see what happens!!!!!!!!! The remaining question, is why the black and gray didnt add a credit??? maybe its line 3 or something.... lets see what happens when I get the buttons hooked up... stay tumed

Now for the thanks!!!!!!!!!!!!!!!  Op bell, dude, your the best!!!!!!!!!!!!!!! or you the man, or bitchin or what ever else says your the best!!!!!!!!

[bob in phx]

ok, final results.

1. the coin entry top/frame is most likely from another game.
2. The software allows you to choose what line you want to play, but only when you want to play with credits!! you can pick the combination of lines to play
3. The origianl single big button didnt work do to the wrong wiring, compounded by me not reading Op-bells color codes right... The switch is actually wired to GRAY with a black tracer and Op-bell suggested that it should be BLACK with a gray tracer. I move the connection over and to the black/gray and it works great.
4. Op-bell is amazing!!!!!!!

My next step is to make a cover plate, add 3 momentary switches and then wire it all up!!!!

Many many thanks to all who looked and helped!!!!!!!!!!

Now where can I buy the little 24volt indicator lights, 24 volt festoon lights and the f14t8 floresents......
bob in phx.

[Op-Bell]

The 24V festoon lights are truck parts, easy to get. The other small 24V bulbs, not so much. They are an obsolete kind of bayonet base. There are only 3 of them, for the lines, plus the one up next to the test switches inside the door. I replaced mine with T1 wedge base bulbs and holders.

[CaptainHappy]

I have to agree about OP-BELL,

I do not think I have seen him stumped yet!

 

and some K+ 

CaptainHappy

[bob in phx]

so, everything iis working as it should now!!! but, I was thinking last night, what would it take to add a spin button to my new control pannel?????? that would really bring this slot into the present day!!! I have room on my new panel.......

All I would have to do is:

1. interupt the resting posiition switch.
2. trigger the Full pull switch.

I would guess that a double pole, single thow, momentary swtch would work fine in this case...

maybe Ill do it!!!!

[Op-Bell]

Aw, you guys give me too much credit. I'll let you in on a secret - the secret of being right all the time is only respond to questions where you know the answer! 

Now as for a start button, this is the code that reads the switches and sets the start flag:

Code:

; called from interrupt
; This debounces an input, sets 3036.7 high
; Very likely the start switch - but 2 bits?
; (at-home switch and pulled switch)
check_start:
        LDAA    PIA_4B                  ; bits 7..3 inputs
        ANDA    #$60                    ; extract bits 5,6
        CMPA    #$60                    ; both high?
        BNE     cACD4c                  ; no
        STAA    start_delta             ; both released, make 3037 nz
        BRA     cACF8c                  ; exit
; one or both of P4B.5,6 are low
cACD4c: LDAA    start_flag              ; mem 3036
        BMI     cACF8c                  ; exit if bit 7 set
        BNE     cACE7c                  ; count running
        TST     start_delta             ; for change of state, must be nz
        BEQ     cACF8c                  ; exit if zero
        LDAB    PIA_4B                  ; read PIA again
        ANDB    #$60                    ; extract bits 5,6
        BNE     cACF8c                  ; exit if either high
; we need both bits low for 20 counts
cACE7c: CMPA    #20                     ; did 3036 reach 20 yet
        BNE     cACF5c                  ; no, increment and exit
        ORAA    #$80                    ; yes, set bit 7
        STAA    start_flag
        CLR     start_delta             ; clear change of state
        BRA     cACF8c                  ; to exit
cACF5c: INC     start_flag              ; inc count
cACF8c: RTS

What that shows is that both switches have to be closed to start, that is, the resting position switch is open when the handle is back, closes when it comes forward, and the full pull switch closes at full pull. So you need a double pole switch to close both of them to ground, or else connect both inputs together - it will be ok.

[hholler]

Hi I am new to the forum and am sorry for hijacking this thread, but since I think I have this identical machine I thought it might be best to keep this altogether. If it isn't then I can make a new thread. Just let me know.

Now to my problem...I got this machine several years ago and have worked on it several times and each time give up for lack of schematics. I found this forum and it looks like several of you might have the knowledge to help.

When the machine is powered up the hopper continuously runs and two or three of the reels will fire and just spin free. The reel mechanism motor is not running. I thought at first I was not getting 24v AC from the powersupply. But a meter check shows that I do have 24v AC out of the Power Supply.

I traced the 24 Vac to the reel mechanism plug at the back of the machine and at that point it seems I only have 14Vac. I jumped 24Vac to the reel motor with it out of the machine and then when powered up the reels do not fire and spin free....the reel motor appears to just lift the arms like it is indexing...which I think is what I want.

So tracing back to the MPU pin 11 appears to be where the 24V out to the reel motor is obtained. I have replaced a burnt resistor....220 ohm which I thought might have been the culprit....but it made no change.

I have an extra MPU board so I tried swapping them out and get the same results....It could be possible that it has the same failed components....highly unlikely.....or that maybe I am looking in the wrong place.

Any thoughts? Am I on the right track? Does anyone have schematics of this unit? I have the generic service manual but it does not give any details of the MPU.

[Op-Bell]

Nobody has a schematic of the CPU, but the generic service manual of which you speak should have a wiring list telling you what lamp, solenoid etc. goes to what pin on the CPU rack, and in a column to the right, which port on which 6821 PIA chip. That helps narrow down a damaged chip. The "transistors" on the PIA board are all triacs, since everything in the machine is 24V AC. Speaking of which ... the 24V AC is NOT REFERENCED TO LOGIC GROUND! It is floating on top of about 18V DC relative to the CPU's ground. So be awful damn careful measuring and rewiring the 24VAC, that first of all you know what your reference point is to get the correct reading, and second that you understand how the motor, solenoid etc is connected back at the CPU so you don't inadvertently blow up the electronics. The 6821 chips are unprotected and can easily be damaged. They are all the same so you could try moving them around and see if the fault moves with them. Also, the game will not function unless the RAM memory (two 5101s) is good and the battery has voltage.

[hholler]

Thanks for the suggestions. I will try to swap the 6821's around and see if that changes anything. I might have some 5101's in some junk boards somewhere. I will try the 6821's first.

[hholler]

I swapped the 6821's with no noticible changes. I will go for the RAM next. I also checked the battery voltage and it was only 1.4v Is that enough or should I pull the pack and charge it with a phone charger? I guess it lost juice since the last time I attempted to fix this @&*## thing.

I have 6 extra processor boards of various condition that I can grab RAM from. In looking through them I did notice that there are three different revisions of the boards. The one in the machine as I recieved it has version 2 and unfortunately the RAM is soldered in. I noticed all the version 3 boards have sockets for the RAM. Also some of the RAM have different chip numbers. The Rev 2 board I have has an RCA chip that looks original with a different number. Another of the spare Rev 2 boards also had the same chips. I will write them down and share in my next post.

OP-Bell...You mention a pin out chart in an earlier post that I don't seem to have in the manual I got with the machine. The manual I have is a bunch of loose pages that it looks like were photocopied. One of the pages probably got lost with the last idiot that tried to figure this machine out. Anyway...do you have a PDF of this pinout sheet?