Brian E. Brzezicki
Copyright 2013
Version 1.00 09/10/2013

Disclaimer
Use this at your OWN risk, do NOT sue me if it breaks your board... if your doing this your board is probably already broken though ;)

Game Board #1 9/10/2013

Problem:

    Owner says game does not work, I dont have any more information than that.

Troubleshooting/dianosis steps:

  1. Noted that board had little metal shards on it. brushed them off, one was a large shard underneath a 74LS367.
  2. Noted a 74LS161 had been poorly replaced. removed chip, added socket and replaced
  3. CPU failed fluke BUS test, had tied address bus lines 3 and 5
  4. replaced 74LS245 at E3 and 74LS244 at C2
  5. Found short, the test edge connector had been scraped by something and shorted too lines together
  6. Fluke passed RAM tests for work RAM and vector RAM
  7. Fluke passwd ROM tests for all ROMs
  8. Board is watchdogging, seperated pin 1 from L6 to determine if it's a vector issue, it is, with pin seperated board stops watchdogging and plays blind. (Thanks to DarrenF on KLOV for this tip)
  9. Still working on board
Game Board #2 9/15/2013

Problem:

    Bought off ebay unknown status
    Some 2114s are missing
    Board has TONS of chips socketed and replaced!
    Visual inspection shows the crystal is broken off
    Reset switch leads are shorted together
    One 74LS367 had a chip with legs bent, fixed and re-inserted

Troubleshooting/dianosis steps:

  1. Snipped off extra wire length on reset switch
  2. installed new 12Mhz crystal
  3. Pulled ROMS and verified, they are asteroids version 2 ROMS
  4. One rom had a pin break off
  5. Installed 2 new 2114s to replace the missing ones
  6. tested 3 game code ROMS with Fluke, OK
  7. tested memory region 0x0000 0x03FF with fluke long test, OK
  8. tested memory region 0x4000 0x47FF with fluke long test, OK
  9. game boots up now but display is messed up, parts are OK others are all over the place
  10. Used HP10529A logic comparator, found 74LS191s at C9 and D9 were stuck high pin 6, replaced
  11. Sounds work great, except "thump" sound, which is more like a click, click.
  12. Found .22uf capacitor @ C35 was missing, replaced, sound works fine now.
  13. Game works now.
Game Board #3 10/24/2013

Problem:

  • Bought off ebay unknown statusQ
  • Game is watchdog resetting

Troubleshooting/dianosis steps:

  1. Put on test bench (without monitor) noted game is watchdogging
  2. noticed burning smell, found that 74LS245 is super hot, replaced
  3. game still watchdogging, tried to cut pin 1 on L6, but chip cracked.. replaced
  4. pulled out ROMs, looks like version 2, reburn with version 3
  5. Did a fluke LONG RAM test of all RAM and a ROM test of all ROM.. OK!
  6. Game still watchdogging, replaced CPU
  7. Game no longer watchdogging
  8. Put in Asteroids deluxe cabinet, game is running but vectors are all messed up<
  9. Game still being fixed
Game Board #4 ??/??/2018

Problem:

  • Game does not work

Troubleshooting/dianosis steps:

  1. RAM long 0x0000 - 0x03FF - errors
  2. RAM long 0x4000 - 0x47FF - errors
  3. It's nearly impossible that all the RAM is bad, something else must be up, , pulled code EPROMS
  4. RAM long 0x4000 - 0x47FF - OK
  5. RAM long 0x0000 - 0x03FF - OK
  6. With this behavior where all the RAM does not work, and then after all the RAM does work, either address selection ciruit is messed up simulating RAM errors, or one or more of the EPROMS are bad and talking when they should not be
  7. Checking ROMS, found F1 bad, replaced
  8. Game works