Battlezone - No picture out of test mode

Reinhard

New member
Joined
Jan 4, 2013
Messages
12
Reaction score
0
Location
Idaho
I am working on a Battlezone that has a perfect picture in Test Mode (no errors reported) but won't run or produce a picture or run out of test mode. No response to Coin switches, Start button is lit solid.

Originally, it was dead. First fix was getting proper power to both boards (reflow edge connector pins etc.). Now have 5.01 at main logic and 5.00 at Aux PCB. No measurable AC ripple. That got it to the 10th beep indicating bad 2114 RAM.

Replaced 2114 which got it up to producing a picture in test reporting a math box error (L). Cleaned and reflowed interconnect headers (a number of cold solders at the end pins).

No more math box error.

137004-001 - all 4 tested good but also swapped with working ones from a working Tempest Logic. Swapped Pokey even though all buttons and joystick switches respond in test. Still no change.

The other odd thing is the 137004-001s are all extremely hot to touch in the center. They don't seem to run that hot in Tempest. Again, still only 5.00vdc to them on Aux PCB. And this is for both the originals and the ones out of Tempest currently on the BZ board. BZ ones are still working fine in Tempest.

I am currently digging to get a Win98 machine going so I can use my old Advin Pilot-U40 to test all the Bipolar proms since I don't have another BZ board to swap with.

Anyone ever see this before? Got any ideas?
 
The 2901 bitslicer chips on the aux board run extremely hot. That is normal on a BZ.

Did you verify your ROMs? (i.e., in an external reader, not the game PCB.) I believe it's possible for you to get a test mode, but have other stuff not working, as this only requires one ROM (I think),
 
Thanks for the reply Andrew,

No, I didn't bother to confirm each EPROM outside the board since my old experience with Atari was they were pretty good at reporting errors. But I will tomorrow.

I also haven't resocketed either board yet. I was debating on the cost of the Highscore hold PCB option verses spending the time to unsolder that many EPROM sockets.

I was actually wondering instead if one of the other 2114s failed, if there could still be another one that passes Power up test but may not perform well when running the program.

I haven't put a scope to it yet to see if its watchdogging. That will be next.
 
Pretty much everyone here (myself included) will tell you that the Braze high score save kit is a no-brainer for BZ boards (and really any board that he makes a kit for honestly, but especially BZ). Bypassing the program ROMs, and saving all 10 high scores is easily worth the $50.

If you haven't resocketed the board, that's a good thing to suspect. Even if you get the Braze kit, you should still replace all sockets on everything but the program ROMs, on both boards. UNLESS your boards already have the gold Amp dual-wipe sockets, in which case a can of DeOxit will get them clean, and you needn't replace them. (I also find you can use DeOxit to clean the crappy quality 'pinch-style' sockets, enough to usually get the board working temporarily, as I like to verify that the board is working with the original sockets first (when possible), before doing a socket replacement.)

Also, just a heads up that there are two versions of BZ ROMs floating around the net. I've tried both, and have not noticed an obvious difference in gameplay, so I cannot say what differs between the two.

The two sets only differ by one ROM, however one of the zip files I found actually has the wrong file for that one ROM. The zip file says it's the v2 set, but the one ROM that is different between the versions has the checksum from the v1 set, which I verified against a mask ROM I had in one of my boards that was clearly labeled 036414-01 (i.e., v1), and had checksum 4263. The v2 checksum for the same ROM is 412D.

Anyway, some random info for you, but maybe it's useful.
 
Thanks again Andrew for the extra info. Every bit is helpful.

So, minor/major update:

Luckily, a friend was able to dig up a set of boards and send them to me. His were a bit of a mess (broken Crystal, water damage etc.).

First I tried his Aux board. Came up in test but with L or H errors depending on how the wind was blowing - still no image in game play mode. So, instead, I tried his Main logic after a bit of clean up and replacing the Crystal with a 12MHz instead of the original 12.096.

No Math errors and it actually came up into game play albeit in French and with some video glitches here and there (Alphanumerics being drawn in the wrong place and Scope sometimes defaulting to a straight Vertical line).

So, my first step was to replace the 6502 socket and the two Video Rom sockets since a bit of board flexing there caused it to freak out. Both Sockets and Chip's legs were pretty nasty from the liquid damage. Used my tested and clean Vroms and grabbed a fresh 6502A.

Put it back in, and now its worse. Video is mostly being drawn in the left 1/3 of the screen as if most of it is off the tube. Even though I feared a bad DAC, next, I replaced all the program sockets and used the ROMs off my other board which all checksumed good and had perfectly clean pins.

Still no improvement. Did I mention there was plenty of liquid damage? Some of which was in the X-Y analog area.

Long story short, human fingers around the TL082 for X drive made the vectors drift in an out of where they weren't being drawn. A New TL082, and a bit of cleaning underneath and now I have at least one working board set.

Now to figure out what's wrong with the other two. I am pretty confident (based on the condition of the other gold, dual wipe sockets) that for the Aux board, it may be no more than having to re-socket the whole board like I did the Main logic. My original Bad main logic remains a mystery since it wasn't any of the roms and the gold sockets are in what appears to be excellent shape.

High Score Save Module just ordered.

Updates to follow.
 
Good update. Congrats on getting the one set working.

L and H errors on the aux board are very frequently bad/dirty sockets, or interconnect issues.

Be sure to verify the interconnect cable, clean the contacts with DeOxit, and reflow the header pins.

FYI, you can soak the boards down with your favorite cleaner (409, Greased Lightning, Simple Green), and gently give them a scrub with a soft paintbrush, which removes most grime. If there's serious corrosion, I've soaked boards in a white vinegar bath for a couple of days, to break up any crust. Put in front of a fan overnight to dry. They'll shine like you won't believe, and be much nicer to work on.

You should consider replacing the video adjustment pots as well. I swap them out with sealed cermet ones, which won't snap off easily, don't get dirt in them, and won't get bumped out of adjustment (as you need a screwdriver to adjust them).

Can you give any more info about your other non-working main board? Symptoms?
 
Two Steps forward and One Step Back..........

So, the Water Damaged board took a dump after burning it for over an hour. So, I went back to work on my original board (symptom: Perfect picture, no errors in Self Test screen, but No picture or operation in normal game mode).

Took the scope to it and found no NMI to the CPU. Bad 74LS161 at L4. New '161 and its working great now. Apparently, via the TEST switch line, it is disabled in Self Test and not required. So, that one is burn testing right now.

As for the Water Damaged one, now, its not drawing valid X and Y vectors so monitor is in spot kill. Its running its program without Watchdog resets. But when put it into test, I get single continuous low Tone. Which is supposed to mean bad VROM at B/C3 but the rom is good, fresh socket (no torn traces etc.) Address and Data signals all look good. I don't think its a buffer issue since the same ones are used to address and R/W to the VRAM (bank of 2114s) and I can force a failure to get high/low tones but after it runs through the normal RAM and Rom testing time frames, it produces the continuous low tone. And then you can hear that it is doing a watch dog reset about every few seconds. I have good signals for Vrom select lines too. So now this one has me stumped.
 
Good update. Congrats on getting the one set working.

L and H errors on the aux board are very frequently bad/dirty sockets, or interconnect issues.

Be sure to verify the interconnect cable, clean the contacts with DeOxit, and reflow the header pins.

FYI, you can soak the boards down with your favorite cleaner (409, Greased Lightning, Simple Green), and gently give them a scrub with a soft paintbrush, which removes most grime. If there's serious corrosion, I've soaked boards in a white vinegar bath for a couple of days, to break up any crust. Put in front of a fan overnight to dry. They'll shine like you won't believe, and be much nicer to work on.

You should consider replacing the video adjustment pots as well. I swap them out with sealed cermet ones, which won't snap off easily, don't get dirt in them, and won't get bumped out of adjustment (as you need a screwdriver to adjust them).

Can you give any more info about your other non-working main board? Symptoms?
 
Back
Top Bottom