It's ALIVE(ish)!!!

TSB

Well-known member
Joined
Jan 14, 2016
Messages
2,541
Reaction score
916
Location
Alaska
The 10529 comparator came in yesterday, so I spent some time on Spy Hunter...

I found several bad ICs right off the bat. Replacing them brought up a screen with just the number 9.


attachment.php
attachment.php


attachment.php
attachment.php
 

Attachments

  • IMG_8244.JPG
    IMG_8244.JPG
    196 KB · Views: 137
  • IMG_8242.JPG
    IMG_8242.JPG
    182.4 KB · Views: 135
  • IMG_8245.JPG
    IMG_8245.JPG
    190.1 KB · Views: 133
  • IMG_8243.JPG
    IMG_8243.JPG
    160.2 KB · Views: 131
  • IMG_8250.JPG
    IMG_8250.JPG
    152.3 KB · Views: 10
Last edited:
There are several ICs that the 10529 can't test, though, so I started piggybacking some of those in an attempt to narrow it down a bit.
Placing multiple 74ls273 gave me a new screen (pic1), so I used a process of elimination to see which ones were making a difference.
These ones (pic2, yellow arrows) made the game start, and I could coinup & play a game! The image still needs work (pic3).
Can anyone narrow this down a bit using experience? Maybe if you've seen something similar and remember what your fix was...

The Video Board and interconnect cables are both known-good, so it has to be something on this CPU Board.


attachment.php


attachment.php


attachment.php
 

Attachments

  • IMG_8246.JPG
    IMG_8246.JPG
    87.3 KB · Views: 122
  • IMG_8247.JPG
    IMG_8247.JPG
    256.6 KB · Views: 124
  • IMG_8248.JPG
    IMG_8248.JPG
    91.1 KB · Views: 124
Last edited:
I just had it come up perfect (pic1), but quickly fall back to this (pic2) before going back to playing "in the snow"...

attachment.php


attachment.php
 

Attachments

  • IMG_8261.JPG
    IMG_8261.JPG
    155.7 KB · Views: 91
  • IMG_8262.JPG
    IMG_8262.JPG
    100 KB · Views: 94
Piggybacked 74ls273 are installed. I get a couple different screens when I power it up now.
1st just sits with the watchdog reset (gif1).
I can reset the machine and get (gif2).
Then resetting sometimes gives me (gif3).

Eventually, a successful boot gives me (gif4).

Anyone with some insight on this?

attachment.php




attachment.php





attachment.php





attachment.php
 

Attachments

  • IMG_8288.GIF
    IMG_8288.GIF
    237.6 KB · Views: 61
  • IMG_8289.GIF
    IMG_8289.GIF
    371.2 KB · Views: 59
  • IMG_8287.GIF
    IMG_8287.GIF
    250.1 KB · Views: 59
  • IMG_8286.GIF
    IMG_8286.GIF
    490.7 KB · Views: 61
Back
Top Bottom