Atari Color Raster Games

I've fixed quite a few Atari raster circuit boards over the years, Centipedes, Millipedes, Missile Commands and some System 1/2 items.  Some of these are straightforward, some more complicated.

Missile Command

 Green Screen on boot (2/25/21)

  1. Board was repaired by my in past, tagged as not working now.  It was watchdogging, used Fluke to test Roms, first Rom was bad at H1, odd as it was new and socketed.
  2. Swapped rom, still fails test, trace back to 7408 at J6, which was socketed already and replaced.
  3. Visual inspection showed pin 5 or 6 of the socket reamed to large, making crappy contact. Replaced socket and now passes Fluke test.
  4. Still not working, test ram and it fails ram test, but no beeping self test mode.
  5. Replaced ram at N4 as activity at pin 14 under Fluke test was different than other rams, board now works with no sound (reason why I didn’t hear beeping, I guess).
  6. Replaced LM 324 as I was being lazy, suspected bad Pokey socket (Pokey was checked).
  7. No change, replace Pokey socket, still no sound, double check external amplifier and swap it out with another, still no sound.
  8. Move board to another test rig and sound works, something wrong a speaker or wiring on the first test rig, go figure.

Board boots to white screen, nothingness (5/29/18)

  1. This was a eBay board, rom sockets were clearly replaced, new roms.
  2. Clock looked good, board was watchdogging.
  3. Ran Rom test using 9010a, everything failed, but signatures were ones I’ve seen before.
  4. Realized Rom order was reversed when installed in sockets.
  5. Reorganized rom order, now passes all roms but N/P-1. 
  6. Visual inspection on bottom of board shows a couple jumpers from one rom sockets were installed, one was loose, fixed it.
  7. Board passes Rom test, but still not doing much.
  8. Ran Fluke ram test at 0-3FFF. Got R/W ERR @ 0000 BTS 60. Replaced P4 and then N4. I think N4 was bad.
  9. Ran ram test again and get R/W ERR @0000 BTS 20. Replaced 4116 ram at M4.
  10. Board now passes ram test and works!

Green Screen on boot (5/16/18)

  1. Swapped original roms with known working set.
  2. Roms H-1 and J/K-1 fails Fluke rom test.
  3. Replaced 74139 at M5, no change.
  4. Replaced 7408 at J6, now passes rom test.
  5. Failed ram test with 9010a, replaced L6 socket.
  6. Boots to Missile Command title screen then crashes.
  7. Replaced POKEY and board now works.

No Sound (5/15/18)

  1. Board was working, sound died in testing.
  2. Used logic problem to check pin 37 at POKEY. Could hear the sounds being played.
  3. Replaced LM324 at N10, sound now works.

No Sound (5/15/18)

  1. Board was okay, but sitting in a box for a while, swapped POKEY and sound came back.
  2. Original POKEY was retested and was  good.
  3. Replaced POKEY socket and sound now works with either POKEYs.

Green Screen on boot on some of the monitor (5/14/18) 

  1. Clock and reset looked good, board was watchdogging, I think.
  2. Used 9010a and found a bad rom (forget which one). 
  3. Replace the rom and board now boots.

Garbage on boot (5/14/18)

  1. Reset was low, bad 74LS14 at D3, replaced, reset now high.
  2. Boots to garbage on bottom half of the screen.
  3. R/W error at 2000 BTS FF.
  4. Couldn’t figure out the rest, board had a ton of work done to it, put it back in the box.

Nothing on boot (5/14/18)

  1. No clock signal, 10mhz crystal missing. 
  2. Replaced crystal, clock is bad, but board is watchdogging.
  3. Connected 9010a, board, Data bus 0 stuck.
  4. Turned board over, cleaned up some chip leads that were bent, retested, Bus OK.
  5. K/L-1 Rom fails 9010a test, replaced it, board now boots but with video issues, screen mostly yellow.
  6. STOPPED HERE

Flashing white screen on boot (was working) (11/6/15)

  1. Boardset was working, clean set from a game I was restoring.
  2. Disabled watchdog and the board went to game mode and worked fine, figured a watchdog circuit issue.
  3. WDOG output at pin 5, E8 (7442 IC) was low, inputs to E8 were pulsing, looked good.
  4. Replaced E8 and the board now works.

Random while blocks on boot (6/12/15)

  1. Started by testing roms using Fluke 9010a and one was bad and replaced.
  2. Tested ram and immediately got errors.  Replaced a couple of 4116 rams but no change, suspected it was not ram.
  3. Started checking DRAM Data Input selector circuit and found MD0 stuck low.  Traced this back to BD0 and eventually a bad 74LS244 buffer at E2.
  4. Passed Rom and Ram tests on Fluke, but still yellow screen, reset line was stuck low.
  5. Spent too much time checking ICs and replacing a couple that were in fact good until I realized 7493 counter at D4 was replaced at some point and a 7490 was installed.  Removed it, installed a socket and a new 7493 counter and board worked.

Random while blocks on boot (2/6/15)

  1. Started by testing roms using Fluke 9010a and some checked out okay, two checked out bad.
  2. Checked Bus with Fluke and was getting bus errors, finally discovered a cap was shorting to trace (at least that’s what I think the problem was).
  3. After spending way too much time figuring out the bus issue I confirmed the roms and rams were okay (replaced a few rom sockets as well).
  4. Board came up but with a lot of green graphic interface, which was due to a bad 82S25 (7489) ram at L7.
  5. Board has no sound.

Nothing on Boot (2/5/15)

  1. Replaced processor socket first a preventative maintenance.
  2. No clock signal, crystal was missing, replaced that to fix clock signal, but still not doing much of anything.
  3. Used Fluke to test roms and found a bad rom at L/M1. 
  4. Replaced bad rom and board fired right up.

White screen on boot, sometimes zig-zaggy white lines (2/5/15)

  1. Replaced processor socket first a preventative maintenance.
  2. Used Fluke to test rams and roms, everything checked, board not watchdogging.
  3. Suspected something in Sync circuit, noticed 128V and 64 Signals were stuck low.
  4. Traced this back to bad outputs on pin 6 and 7 from 74LS161 counter at B4.
  5. Replaced B4 and board powered up with trackball issue. Cursor would not come back down after going up.
  6. Tried shotgunning this by replacing C9, C11 and D9, but no change. Finally found it to be 7474 IC at J8 that was causing the problem.

Board Marked as Non repairable with a short (2/5/15)

  1. Board had some work done, number of sockets replaced, all buffers replaced, but was missing roms and rams. Was tagged as “Not Repairable” by a board repair guy I used years ago.
  2. Burned new set of roms and installed 4116 rams.
  3. Roms pass tests on Fluke 9010a, but fail the first ram test (4116 rams).
  4. Test mode reports K4 bad, but swapping it out led to no change. Once and a while it would report another bad 4116 ram as well.
  5. Took a while but traced this back to a bad output on H3, pin 9 was stuck low. Replacing 74LS153 at H3 fixed the ram errors in self-test, but board still didn’t work, booted to white bands on screen.
  6. Retested ram with Fluke 9010a and board passed all ram tests.
  7. Started at Sync section, everything looked good, moved further down schematics and found M7 pin COLNUM2 was stuck low at pin 14.
  8. Traced this back to dead LD2COL input at pin 9 on N7 (and M6, pin 9), which was caused by bad 74LS175 at C7. Replaced C7 and board booted with input issues, second player started not working, trackball not going left or right.
  9. Replaced 74LS191 at K9 to fix the Player 2 Start button issue, but still having issue going left.
  10. After replacing almost every IC in input circuit (figured it was C9 or D9, but it wasn’t) finally using logic probe I found that K9 pin 3 was shorted to ground. This was due to a bad 74LS244 at L9.

Millipede Repair Log

Nothing on Boot

  1. Reset signal was stuck low.
  2. VBLANK and WATCHDOG was not pulsing.
  3. 8F looked good, went back to Vertical Sync Chain and tried replacing 8E as it looked rusty, no change. Also replaced 7D, but no change.
  4. Replaced prom at 7E and reset signal came back to high, game came up, but a big white band in the middle of screen only the top and bottom lines of text were visible.
  5. Game did play with sounds, just nothing on 98% of the screen, ran 9010A tests on program rom, program ram and video ram, everything checked out okay.
  6. Started probing around Line Buffer area of schematics, noticed a number of outputs were stuck high at 9B (GRY0, GRY1, MOCB1, MOCB2). Replaced 93422 Ram at 8B as inputs looked good here, but no change. Replaced 9B, still no change.
  7. Starting moving further down schematics Color Memory Address Selectors and replaced 9C, still no luck.
  8. Moved onto Motion Object Color Selectors portion of schematics and piggybacked 8J, screen cleared up a bit, replaced 8J (74LS153) to fix the problem.  
  9. Probably should have piggybacked these ICs first, but live and learn.

Centipede Repair Log

Always put game in self test and check rams as this is a very common problem.

Board comes out of sync (1/27/16)

  1. Tried board on Jamma test bench (uses negative sync as opposed to positive sync on my harness) and it came up okay.
  2. Checked outputs for positive sync and they were stuck high.
  3. Traced back to 7407 at A/B10, inputs looked good.
  4. Replaced 7407 at A/B10 to fix the problem.

Board boots to blue screen (3/25/15)

  1. Noticed  Q5 had a broken leg, replaced it (2N3904)
  2. Board now boots to garbage.
  3. Board was watchdogging, clock signals looked okay.
  4. Fluke reported bad 307 Rom at D1. Removed and reinstalled and then reported it as okay.
  5. Replaced rom socket at D1, board still booted to garbage.
  6. Replaced processor socket as I’ve seen these style of socket be problematic.
  7. Boards now works, but cursor goes right on game play and stays there (will move using trackball during game play but then reverts to right edge of screen).
  8. Also while testing went back to garbage on screen.
  9. Found bad rom socket at Rom 310.
  10. Right issue was due to….

Board boots to green screen (3/24/15)

  1. Boardset was watchdogging, clock signals looked okay.
  2. Fluke reported program ram errors, replaced both 2114 rams at H2 and F2.
  3. Board comes up with video issue (characters on right side of screen).
  4. Stopped here

Board sometimes reports bad rom at F/H1 (3/24/15)

  1. Seemed to work sometimes or was close but was reporting a bad rom at F/H1 sometimes, suspected bad rom socket..
  2. Replaced rom socket and then used Fluke 9010a and it still reported a bad rom.  
  3. Replaced Rom 209 and it booted and played fine on Jamma test bench with Centipede adapter.
  4. Moved to Centipede test rig (using original Atari harness and power supply setup) to test track-ball and lost sound.
  5. Replaced LM324 at J10 and sound returned to Centipede test rig.

Board boots with video issue (3/24/15)

  1. Put board in test mode and it beeped three times.
  2. Replaced 2101 ram at K7 and board now works.

Plays, but Garbage Letters on Screen (2/28/12) –  Put game in test mode and it reported  Ram K7, replaced this and it then reported Ram M7 bad. It looked like M7 was already replaced (but not socketed).  Removed M7, installed socket, fixed broken trace from prior repair and put a new  2101 Ram and the board worked.

Plays, but Garbage Letters on Screen (2/29/12) –  Put game in test mode and it reported  Ram K7, replaced this and it then reported Ram L5 bad.  Replaced Ram L5 and the board came up fine. 

Video Issues, Zeros on Screen, No Sound (2/28/12) – Game would play, but there were zeros on the first screen. Reseating the character roms and the problem went away.  There was still no sound, checked around LM324 amp and found that the output was dead (input was dead too, but I assume the LM324 was causing that).  Replaced LM324 and sound came back.

No Sound (2/29/12) – Didn’t even bother troubleshooting, just replaced LM324 amp and the problem was fixed.

Garbage on Screen (2/29/12) – Board booted with some random characters on screen.  Tried test mode, but realized test switch was stuck on, replaced test switch, still garbage, nothing from test mode. 

Marble Madness Carts

Cart Booted with Rom 20000 Error U (3/16/16).  Manual indicated this error was 15E, but that didn’t correspond with the version of the cartridge that I had.  Checked the manual and determined it was a program rom at B12. Burned a new rom and the board then booted to 6502 not responding error.  Did some rom swapping and found a bad sound rom at D16, replaced this rom and the boardset worked.

Cart Booted with Bank Switch Error (12/21/11) – checked the two slapstic roms (107 and 108) and one was bad. Replaced rom and game booted with 6502 Not responding error.  Starting checking other roms -401 to be bad. Also found a bad sound rom. Replaced these two roms and the board works fine.

Cart Booted with No Cartridge Error (12/21/11) –Starting checking the roms and found bad roms at -404, -403, -401 and a bad sound rom.  Board now comes up with video issues.  Starting swapping other roms and they were all good. Moved onto Atari custom chips 137415-1 and starting testing those in a known good board.  Found one bad one, replaced this and the board still has issues.  Moved on to the two PROMs and found one bad.  Board finally works!

Atari System 1 Cartridges

Indiana Jones Carts

Card boot with Rom at 28000L and 20000L Error (8/19/2020) – Both errors corresponded to bad rom at 12A. Pulled rom and cleaned legs, reinstalled and board now boots with dots on background of title screen.

Starting pulling and test roms and found rom at 4C (136) was bad. Installed new rom and board works fine.

Cart came up with ”Farting” Noises (12/22/11) – Video looked good, but game was making farting noises at boot, no real sounds.  Replaced TMS5220CNL from another board at location 16H and the problem was solved.

Road Blasters Carts

No Cartridge Error (8/21/20)- Quick visual inspection showed that rom A11 was missing. Grabbed one from another board and it board booted up fine.

Game would boot with blocky Graphics (2/2/12) – Bad Prom at 7A. Replaced with a good Prom and the problem went away.

Road Runner Carts

Game would boot, background graphics corrupted, character graphics off (2/2/12) – Bad Slag at 5H, replaced with another and the problem went away.

Atari System 2 Repair Log

720 CPU (3/9/21) – Popping and won’t coin up.

  1. Quick schematic checked showed TMS5220C at 7D near coin input and speech circuit. Swapped that into working board and it produced same bad effect.
  2. Replaced TMS5220C and board now works.

Super Sprint CPU (12/8/17) – Board booted to garbage on the screen, clock signal looked good, reset signal was low (normal) and data lines were moving. Checked program roms and ram, but they tested good in another boardset, which I expected. Was puzzled on this one as it seemed to be behaving normally based on other boards I looked at it.  After some probing around found that 14.318 crystal had a broken leg, replaced the crystal and boardset booted fine.

Super Sprint CPU (12/7/17) – Board booted to garbage on the screen, clock signal looked good, but board was watchdogging.  Checked program roms and ram, but they tested good in another boardset.  Pressing on the TII processor during boot-up got the board to show signs of life.  Replaced processor socket and board played fine.

Paperboy CPU (12/6/17) – Nothing on screen, just some white raster.  Quick inspection showed some traces that were scratched.  None were cut, but two were smashed together and shorted. Cleaned up the area, retested the board but still nothing. Clock signal looked good, reset line was watchdogging.  Swapped program roms and rams into known working board to find bad 6116 at 6P.  Board now boots up and plays but has a sound issue.

Self tested reported bad rom at 2D, replaced it but sounds were still off, but no longer reporting that error. Started swapping sound ICs and found bad YM3012 on row 8. Replacing that fixed the problem.  Rom error 2D popped back during testing, replaced socket and it is started working again.

Paperboy Video (12/7/17) –  Board booted with video issues. Swapping roms into known working board and found rom at 6T to be bad. Burned new rom to fix the problem.

Paperboy Video (12/7/17) –  Lines in the “paperboy graphic” on the newspaper screen.  Pressing on roms showed that it went away when I pressed on one.  Removed rom, cleaned legs and reinstall to fix the problem (forget which rom it was).

Paperboy CPU (12/6/17) – Nothing on screen, just some white raster.  Quick inspection showed some traces that were scratched.  None were cut, but two were smashed together and shorted. Cleaned up the area, retested the board and it came back to life.

Paperboy CPU (12/6/17) – Board booted with random specks of garbage on screen.  Removed T11 processor and reseated it, board came back to life.

APU CPU (12/6/17) – Board booted to garbage.  While checking program roms, noticed that two were in the swapped in the wrong location, moved them back to the proper location and the board booted fine.