Defender troubleshooting help

[kstillin]

You can 'compare' them here-

www.coinop.org/RomId.aspx

Load the eprom file to your computer, point this webpage to them, and it will tell you if it's a Defender ROM image or not.

Hi,

I just got my programmer working and I need Rom images to compare my roms to. I see references to mame roms but assume these are not working roms. I have red label roms. My Rom 11 and 12 both have some gaps or 11 00 lines at the start of the rom and mixed within. The legs from my second set of roms were so brittle that they fell of when i removed them so no good to compare.
Could someone point me in the right direction to get this code?
Thanks
Dan

 

[YellowDog]

Hi,

I just got my programmer working and I need Rom images to compare my roms to. I see references to mame roms but assume these are not working roms. I have red label roms. My Rom 11 and 12 both have some gaps or 11 00 lines at the start of the rom and mixed within. The legs from my second set of roms were so brittle that they fell of when i removed them so no good to compare.
Could someone point me in the right direction to get this code?
Thanks
Dan

Hi Dan,

The MAME ROM images are the exact images you need. You just need to find the Defender red label zip file and unpack it.

I'm going to go out on an limb and guess your second set of ROMs were the TI EPROMs with the gold plated legs. I rarely find a complete set of those where the legs haven't rotted off. If there is enough left, you can clip legs from a different chip and solder them on. The prothetic legs won't stand up to a lot of abuse, but they should be good enough to check the data on them.

Steph is correct. Defender is the only one of the Williams classic games that uses different sizes of ROMs, so you need to make sure your EPROM burner is set to the correct type before you try reading them.

As far as finding the MAME images, just Google 'MAME Defender'. That should get you to one of the many MAME repositories on the net. There are some scam sites out there, so if they ask you to pay to get the images, go somewhere else. There are plenty of free archives.

ken

 

[dandydan1959]

Thanks for the good info

Steph called it right when he said that I checked them as 2732's My Rom checker will not do 2532 so I may be back to square one. Yellowdog was also right on the legs issue. They fell off like they were so corroded that they could not have worked. I have a blended set of roms now. I have red factory labels mixed with white labels with red marks. I thought they were the same but am learning that this assumption is not a very good one to make in this hobby.

I am stuck with a board that boots past the rug to lights two and four on the Rom board on. Going to order some ram from somewhere. This machine is starting to be a money pit. Funny how good it looked when it was in someone elses garage. Now that it is my shop and being a pain it is a different story. I always wanted to own a defender.
Now I am not so sure.

 

[dandydan1959]

Going to ditch the 4116hi,

Hi,
I am going to ditch the 4116s. My symptoms change so often something has to be wrong besides Rome. Should have done that right from the start. Found a source for 41256 for .50. each. I see posts that say with a mod this ram can be used.

I will update when I have new ram and mods done.
Thanks for the help.
Thanks,
Dan

 

[YellowDog]

You can build an adapter for 4164s. It looks like the pinouts are compatible. There is a document on how to build a power adapter here: http://www.robotron-2084.co.uk/techwilliams4164.html

ken

 

[LeChuck]

This machine is starting to be a money pit. Funny how good it looked when it was in someone elses garage. Now that it is my shop and being a pain it is a different story. I always wanted to own a defender. Now I am not so sure.

I would argue that this statement applies equally well to almost any hobby Reminds me of when I pulled the hand brake a few clicks too far in my VW Beetle. Next thing I knew it I was replacing the cables .. and the brake bleeder valves .. and all the brake lines .. and the brake cylinders .. and the shoes .. and rear axle seals .. and ..

Keep plugging away, soon you'll have it running again (and kicking your butt)

LeChuck

 

[dandydan1959]

help with Ram

Hi,

I found some 21256 locally and after reading the site www.scoresaves.com/misc/JustSayNoTo4116.html I performed the mod as documented on that site.

I cross checked the 21256 with the 41256 and I believe they are direct replacements.

I also found that my ROM 3 was bad on the ROM board, a leg fell off, this was a chip that the legs had turned black. I replaced the ROM 3 with a 2732A and the cross checked the checksum to be sure I had a good burn.

When I power up the game it does not appear to be powering up correctly. I unplugged the ROM board and when powered up the mpu without the ROM board attached the video is scrambled instead of black and white alternating bars.

I think the mod for the 21256's is a problem but I am not sure.
Has anyone tried the mod and tried 21256's?

I may go back to the 4116's since I had a good board at one time.
Thanks
Dan

 

[steph]

Hi,

I also found that my ROM 3 was bad on the ROM board, a leg fell off, this was a chip that the legs had turned black. I replaced the ROM 3 with a 2732A and the cross checked the checksum to be sure I had a good burn.

Rom 3 is a 2532.
A 2732 has a different pinout and won't work.


Steph

 

[YellowDog]

Did you do all 4 parts of the mod?

There are 2 traces that need to be cut and 2 jumpers that need to be attached to run 41256 RAMS.

It would probably be easier to make the adapter than to be cutting and patching the board. That way you can freely go back and forth between 4116, 4164 and 41256 RAMs by taking the adapter off, putting a 4164 adapter on or putting a 41256 adapter on.

ken

ken

 

[dandydan1959]

Hi Guys,

Rookie mistakes for me.

I was trying to use the 2732A in the Rom 3 slot. After the advise on the board I built the adapter from Bob Roberts site and using the Willem 5.0c EPROM programmer it still won't reliably read and repeat the check sum correctly. This programmer is not for the older hobbyist looking for a solid, consistent, reliable programmer for the older stuff. I have not been able to get a 2716 or a 2732 programmed as of yet either. Reads them fine some of the time.

I also understand the 2732A is a different programming voltage that a 2732 so beware of that when you are starting to work with these things.

I pieced back together ROM 3 by soldering legs back on when the pins had separated. That seemed to work and I am back to a good rug pattern repeating on one of the two CPU's. The ROM board lights all come on and then go off after a few seconds and then light two and four come on and then are cleared and then come back on again after a few seconds of being off and remain on. This does not seem to match any of the troubleshooting codes..

the second MPU I have has no pulsing on the data or the address lines. The E and Q clocks are running and the reset button takes pin 37 on the CPU low and then returns to high. I replaced the CPU and no change. I am going to go follow the clock circuits around some more.

I am learning quite a bit on this repair. The biggest thing is that cheap tools are just what their description says. The stuff from China looks good on paper. Working good is another question.
Thanks for everyone's willingness to provide input and corrections. This site is better than going to therapy which at least on a couple of occasions while working on this game I have considered.
Thanks.
Dan
Dan

 

[dandydan1959]

help with Defender

Hi,

I have a new defender that I am working through issues on. I started with four leds on constant and no rug pattern. I found light acid damage and repaired that and replaced sockets near that area. I now have a rug pattern test and four lights come on for a few seconds and then flash off and the I see from left that the first and third leds light for a moment and go off and then the second and fourth from left light and stay lit. Been about twenty five years since I repaired one of these and I am not sure how to interpret the leds. I have the operators manual and I can not match the patterns.

0= on and X=off

First all 4 on OOOO several seconds
Then 1 and 3 0X0X just a couple of seconds
Then 2 and 4 X0X0 remain lit

I have changed romboard, checked rom checksums, changed ram, changed power supply,
Can someone tell me if the pattern i am seeing is valid for troubleshooting?