Edward Randy PALs and repair log

kyapiko

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Hi guys,

I got an Edward Randy with no video and found a PAL with no signals on all of its outputs (the one located at N5).
As PALs from this game are not available yet on the JAMMArcade PAL archive, I was wondering if anybody would have these ones or may be able to dump them.

I've checked with the same PAL from Robocop 2 and Caveman Ninja (they are running on a very similar system/PCB layout) but they seems to be different. (< in fact no, see below)

Thank you for any help !
 
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I wanted to update my post because, with the help of Shoestring, we managed to find that the PAL on location N5 from Caveman Ninja and Robocop 2 are finally identical, but also that they are identical to Edward Randy.

My board had issues I didn't expect... I will explain here how I managed to fix it.

First, I had a black screen due to a bad PAL on location N5. I replaced it by a hypothetically identical one from Caveman Ninja (or Robocop 2, they're the same).

Here is what I got with it plugged in (that's why I firstly suspected these boards were using different PALs):

edrandy4.jpg


Shoestring told me that it may be caused by an other failure than a wrong PAL.

I started looking for issues and noticed that bending the board made the garbled graphics changing, even making them better looking at some point.
So I suspected the two custom SMC labeled "55" having bad solder joints and reflowed the solder on them.

It then went way better. I had clean backgrounds in game, full intro with clean texts and pictures, title and Data East logo appearing but no sprites in game (there was a square on the bottom-right corner by the way that seemed containing garbled parts of sprites).

I then managed to find where the sprites part was located on the board and found two 6116 RAMs on locations N9 and M9 that had suspicious outputs (pulsing but weakly and at low voltage). Piggybacking a known good working compatible RAM (2018) made parts of garbled sprites randomly appearing on screen.

I then desoldered one of the two RAMs (at location N9). With no big surprise it was tested bad on my programmer. I soldered a socket and put a new RAM in place. There was still no sprites but the garbled square on the bottom-right corner was not there anymore. Outputs on the new RAM were looking pretty much better though with strong pulses at 5V. The RAM located at M9 still showed weak outputs so I replaced it with another good known RAM and sprites magically appeared !!

edrandy5.jpg


I played it to the 3rd level and it seems everything is working fine. :)
 
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Good job.

Thanks to jedutil I was able to see that the PAL equations between the different boardsets were identical.
 
Nice fix.So I think we can add this PAL on jammarcade specifying it the same.
Could you, please, tell me if also other PAL are shared with Robocop 2 and Caveman Ninja?
 
According to the site Robocop2 has 5 Pals & Cninja has 6. I don't know if this is a mistake or if layouts between the boards are different but some of the locations in the filenames are different anyway.

cninja-tj01-h9.jed & Robocop2-PLHS16L8AN.H9.jed are identical.

I can safely say that J9 are not the same. The equations for the inputs that enable output pin 19 are different. Definitely not the same programming.

I think we just got lucky with N5 :)
 
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