I bought this machine working but dirty, and the bottom half of the display out. I figured... no big deal it's working

- I can fix the display,
- It's only a little battery juice on the board. Hahaha
- It's not that bad
- I might as well change the 6116 out and put a socket in for nvram while I'm at it

Well here I am,

I've tried everything in the caseydanger Black Knight 2000 won't boot post. Can't get the Leon to boot.

Everything in the - DumbAss " If a Leon does not work then you can shotgun ICs in the address bus, data bus and address decode but the first thing I usually do is verify ALL the connections in the address bus, data bus." Can't get the Leon to boot.

Everything in the- https://www.pinwiki.com/wiki/index.php?title=Williams_System_9_-_11#System_11A.2C_11B.2C_11C_games Can't get the Leon to boot.

Everything in the- https://techniek.flipperwinkel.nl/wms11/index2.htm Cant get the Leon to boot.

I even tried to give it to #chrishibler to fix.

" Thanks for the pics.
I’m going to pass on that one.
Too much corrosion and rework already.
Sorry.
Chris"

Oh, it's ugly. I hear you. But I have made it through the whole "Leon Tutorial" 20210815_185806[1] (resized).jpgAll voltages are good for all address and data lines. No shorts. All I see is a lower voltage at the PIA's #25 at 1.9v.

So... should I just give up on this board ?? I would really love to fix it and keep the original board. Can anyone out there walk me through fixing this thing?

Rob

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Thanks Chris. Frustration and alcohol got the best of me the other night

Yes, Reset is good at U15. Low then goes high when turned on.
Clock is pulsing
5v. is good and solid ground at the 6802
All inputs and outputs pulsing at U11 and U13 ICs (74ls244's) Hi and low lights on with pulse. Is that right?

I have all the time in the world. Its just a hobby and lots of fun too! This is the most frustrating part though. Data and address lines and horrible schematics.

I'm close to a decision.

Please help!
bump

So, I went with the shotgun approach. U41 (which looked pretty bad anyway) , U42 , U51, U11, U13, U16, U18, U31, U32, U37, SR2, and SR19. Still the same, cant boot the Leon test no diagnostics light. Although it does pulse dimly when I put a test lead on pin 6 of U51

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I went through the "Black Knight 2000 wont boot" thread by caseydanger from a year ago as he was having the same problems as I am. As they were tracking down the data lines in the IC's DumbAss mentioned that U28 was for the 1-8 solenoids and I remembered I was having issues with some solenoids being locked on but wasnt worried about it until I fixed the board. Thought it was a bad diode or something.

Well now probing U28 with the Leone chip in has me finding pins 2,5,6,9,11,12,15,16,19 all the outputs I presume, ( labeled 10,20,30,40,50,60,70,80 on the scheme) are all stuck high and all the data inputs are pulsing. Is this how these pins are supposed to be or did I find something wrong with U28? U19 and U20 have been replaced.

No help still?

Well, my order came in and I installed a new socket and chip at U28 with no change. So I decided to start back at the beginning with the Leon Borre Test.
I changed the 6802 to a new one also with no change.

" Still doesn't work ? Then check these pins: 2, 3, 8, 35, and 40 they all have to be positive (around 4 volt). On pin 39 there's the clock signal, on pin 4 IRQ and on pin 5 the VMA signal, and on pin 37 signal E (syncro for external parts) these all have to be around 2 to 3 volts (measured with a DMM). They are moving signals, here you find some examples of them."

PIN 2=3.1v
3=3.1v
8=5.1v
35=5.1v
40=5.1v

Is this a big difference of these voltages or are these measurements in spec?

Pin 4=3.5
5=3.1
37=2.2
39=2.2

So because of the lower voltages on some of these I was looking into pins 2 and 3 on the schematic and seems pin 2 goes to something called HA17?
And pin 3 goes to something called MR? I haven't seen anything written about these. I have replaced the 4.7k SR2

Also i have a question about the meter I'm using Fluke 113. If I test these pins without changing the range from auto it shows 0v but seems to flash in time with the test chip on most of the points but not all. Is this something I should pay attention too or just a weird DMM situation?

If someone could help me out I think I could get this working. I so close.

Well , I never did fix this board but I did build a new 11b board from DumbAss and it works perfectly.

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