(Topic ID: 254399)

Hollywood Heat - Stopped booting after NVRAM


By MaxAsh

7 months ago



Topic Stats

  • 107 posts
  • 18 Pinsiders participating
  • Latest reply 6 months ago by pincity
  • Topic is favorited by 1 Pinsider

You

Linked Games

Topic Gallery

There have been 8 images uploaded to this topic. (View topic image gallery).

Untitled (resized).png
20190706_213249_resized_1 (resized).jpg
That_Resistor (resized).jpg
2019-10-29 07_17_14-Internet Pinball Machine Database_ Premier 'Hollywood Heat' Images - Internet Ex (resized).png
HH_CPU2_nvram - Copy (resized).jpg
HH_CPU3_socket - Copy (resized).jpg
HH_CPU1 - Copy (resized).jpg
2019-10-28 10_12_15-https___www.pinitech.com_product_images_ram_locations_ramloc_gottlieb80.jpg - In (resized).png

There are 107 posts in this topic. You are on page 1 of 3.
#1 7 months ago

Hey All - while working on another issue with my Hollywood Heat (Gottlieb System 80B), I seem to have done something to cause it to stop booting.

I removed the battery last night, removed the 5101 RAM, socketed the position, and installed NVRAM. I've never had an issue doing this in all the machines I've added NVRAM to, so when I hooked everything back up and powered it on, I was surprised to find it's not booting up. I get GI and attract mode lighting effects, but no tone, no display, game won't coin up or play. Solid red light on CPU board currently. The fact that it's in a form of attract mode seems good, but I'm at a loss as to what I might have done to kill it.

#2 7 months ago
Quoted from MaxAsh:

Hey All - while working on another issue with my Hollywood Heat (Gottlieb System 80B), I seem to have done something to cause it to stop booting.
I removed the battery last night, removed the 5101 RAM, socketed the position, and installed NVRAM. I've never had an issue doing this in all the machines I've added NVRAM to, so when I hooked everything back up and powered it on, I was surprised to find it's not booting up. I get GI and attract mode lighting effects, but no tone, no display, game won't coin up or play. Solid red light on CPU board currently. The fact that it's in a form of attract mode seems good, but I'm at a loss as to what I might have done to kill it.

I had a Data East that was doing some odd things on boot till I did the following- Booted it up with the battery connected and the NVRAM and shut down and then disconnected the battery. Can you hook a battery back up long enough to start, make some setting changes and shut down again?

#3 7 months ago

That won't risk damage to the NVRAM? Not sure how the power situation works on an 80B when it comes to that.

#4 7 months ago
Quoted from MaxAsh:

That won't risk damage to the NVRAM? Not sure how the power situation works on an 80B when it comes to that.

1) Your dead in the water anyways.

2) Worked fine on my DE, which is still running months later.

#5 7 months ago

I don’t know. But I doubt it would kill the nvram

#6 7 months ago

Okay, thanks. I'll see if I can reattach it via jumpers temporarily I guess.

Any other thoughts / suggestions? The last two 80B games I did NVRAM on there was no issue.

#7 7 months ago

It might just be standard 80b stuff. How are the connections to the daughterboard?

#8 7 months ago

System 80 uses both chipselect inputs from the 5101 SRAM IC (/CE1 and CE2) which differs from Bally 2518 and Willams system 6-7 designs which can be used with the single chipselect input from the Ramtron Ferro RAM (NVRAM).

You will need an NVRAM adapter with some additional logic gates "glued" to the NVRAM chip creating the 2nd chipselect input. Did you buy such a "dual chipselect" version? A module with single chipselect input can cause collissions on the data bus and in this way hang the system.

Williams system 3 and 4 are the other exceptions needing a dual chipselect by the way....

#9 7 months ago

Which NVRAM did you install?

I installed (3) 5101 from Pinitech on System 80/b games with no issues.
https://www.pinitech.com/products/5101_nvram.php

You changed the correct part location Z5?
2019-10-28 10_12_15-https___www.pinitech.com_product_images_ram_locations_ramloc_gottlieb80.jpg - In (resized).png

#10 7 months ago

pinballmaniac40 I purchased the "5101 DUAL CE Battery Eliminating NVRAM" from Andrew's site http://nvram.weebly.com/

Yep, I removed Z5, socketed it, and installed the NVRAM in the correct orientation. I checked the connections/traces, they all seem okay.

To answer the daughterboard question, it looks like someone may have reflowed it in the past already. Everything looked solid, and "pushing on it" didn't change anything.

#11 7 months ago
Quoted from MaxAsh:

To answer the daughterboard question, it looks like someone may have reflowed it in the past already. Everything looked solid, and "pushing on it" didn't change anything.

Sometimes you have to push on it in different places as you turn on the game. If that still failed, try another spot and turn it on again. There was only one small area where I could push on at the time that would allow my Gold Wings to boot.

#12 7 months ago
Quoted from MaxAsh:

I purchased the "5101 DUAL CE Battery Eliminating NVRAM" from Andrew's site http://nvram.weebly.com/

I do not have any experience with that one in particular from him, thought I had bought some other type for system 11 and WPC.

Do you have an old 5101 RAM you can try?

#13 7 months ago
Quoted from PinballManiac40:

I do not have any experience with that one in particular from him, thought I had bought some other type for system 11 and WPC.
Do you have an old 5101 RAM you can try?

I've used his 5101s in several games without issue, but I guess it's possible I got a bad one. I'll dig through my parts for another old 5101, but I doubt it.

I pulled the board just now and checked all my solder work, and verified continuity from both the NVRAM side and bottom side to all the respective termination points. All came up good. I tried Gary's battery idea just for kicks, nothing there either. Still just booting to attract mode + GI lighting and nothing else.

I pushed on the daughter board in several places as suggested, no change. Question: Is it the where the daughter board is soldered to the main board that's the problem, or is it the PROM socket on the daughter board itself that has issues? Would I need to remove the whole daughter board and reflow the underside of it?

#14 7 months ago
Quoted from MaxAsh:

Question: Is it the where the daughter board is soldered to the main board that's the problem, or is it the PROM socket on the daughter board itself that has issues?

Any of the solder joints related to the mounting of the daughter board is suspect more than the PROM socket, but it can be that too.

#15 7 months ago

I found a Sharp brand LH5101-45 and an Intel? P5101L-3 in my "removed parts" pile from doing other NVRAM installs. Not sure if the Sharp one is valid.

#16 7 months ago
Quoted from MaxAsh:

I found a Sharp brand LH5101-45 and an Intel? P5101L-3 in my "removed parts" pile from doing other NVRAM installs. Not sure if the Sharp one is valid.

I tried both, no change at all. So I'm guessing it's not the RAM itself that's the problem. I guess I need to go back to basics. Suggestions on what to start with, testing-wise?

I've got 5.06V at the 100uf filter capacitor by J1, so power is getting there.

#17 7 months ago

OK -- 5V at the board input but need to know what the voltage is at the 5101 socket.
Probably difficult to measure at Z5. Z4 uses the same power - measure voltages between pins 14 and 7.

If that is ok -- what is voltage at pin 4 of Z4?

#18 7 months ago
Quoted from G-P-E:

OK -- 5V at the board input but need to know what the voltage is at the 5101 socket.
Probably difficult to measure at Z5. Z4 uses the same power - measure voltages between pins 14 and 7.
If that is ok -- what is voltage at pin 4 of Z4?

g-p-e Measuring Z4 between 14 and 7 the reading is 4.50V , Measuring at Z4 pin 4, also 4.50V

Measuring at Z5 is actually easy on the NVRAM, it's even labeled in the model he makes. I tested Z5 between pin 8 and 22 and I'm getting 4.50V there are well.

#19 7 months ago

So you have a 1/2 volt drop across CR34 -- that's normal.

Plenty high enough for the FRAM. There is a second IC on that board. It *might* not like lower voltages.
It might be a 74HC type part which is OK with lower operating voltage but is pickier with the input logic levels.
Could also be a 74HCTxx type part - doesn't like low operating voltage levels but is less picky with input logic levels.

As long as you *do not* plan on going back to using batteries, you can short out CR34 to bring voltage levels up a bit. Might try temporarily shorting CR34 to see if it helps.

#20 7 months ago
Quoted from G-P-E:

As long as you *do not* plan on going back to using batteries, you can short out CR34 to bring voltage levels up a bit. Might try temporarily shorting CR34 to see if it helps.

Shorting CR34 didn't seem to have any effect, unfortunately. Do you want me to short it, then check those voltages again to see if they changed significantly?

#21 7 months ago

How about posting a picture of the MPU board?

#22 7 months ago

Sure, here you go. If you want more detail, or the back of the board, please let me know. (Note: on the "before" pic with the battery still attached, and original RAM still there, I know that the connector on the bottom is partially off. I decided to take the pic as I was starting to take the connectors off to remove the board).

HH_CPU1 - Copy (resized).jpgHH_CPU2_nvram - Copy (resized).jpgHH_CPU3_socket - Copy (resized).jpg
#23 7 months ago

I don't think the game will boot without the reset board plugged in since this is a system 80B. Normally, it is plugged in just to the right of the MPU, which currently is showing missing in the pictures.
2019-10-29 07_17_14-Internet Pinball Machine Database_ Premier 'Hollywood Heat' Images - Internet Ex (resized).png

#24 7 months ago
Quoted from PinballManiac40:

I don't think the game will boot without the reset board plugged in since this is a system 80B. Normally, it is plugged in just to the right of the MPU, which currently is showing missing in the pictures.

Depends on the game I'm told but all three of my Sys80B games it is unplugged and they all work fine.

Question Max- Did you ohm out the pins on the socket to make sure they are all have continuity to their destinations?

#25 7 months ago
Quoted from PinballManiac40:

I don't think the game will boot without the reset board plugged in since this is a system 80B. Normally, it is plugged in just to the right of the MPU, which currently is showing missing in the pictures.
[quoted image]

It's never had a reset board, and booted fine before I did the battery removal and Nvram install. I had another 80b without one as well. I don't think that's the issue, at least I hope not since there isn't one in this game!

#26 7 months ago
Quoted from gdonovan:

Question Max- Did you ohm out the pins on the socket to make sure they are all have continuity to their destinations?

Yes, I always check that after installing a socket. After this had trouble, I pulled the board and rechecked. All test good from what I can tell. I checked from the solder side, as well as the nvram side. Andrew's design gives you a layout of all the pins topside, you can test right on them, and they're even labeled as you can see in the pics, it's great.

#27 7 months ago
Quoted from MaxAsh:

Andrew's design gives you a layout of all the pins topside, you can test right on them, and they're even labeled as you can see in the pics, it's great.

I just purchased two boards from him this weekend- I have a Haunted House with bad 5101 ram and a Secret Service still sporting batteries, which I want nothing to do with.

The Haunted House has been challenging; MPU had battery damage, bad display chip and now the ram. I'm actually considering getting a hakko desoldering gun if I'm going to keep delving into board repair.

#28 7 months ago

Have you tested all the pins to adjacent pins on the IC socket to be sure too much solder did not flow thru to the top side shorting out adjacent pins?

#29 7 months ago

System 80B games will boot up with no 5101 (NV)RAM installed. Remove the NVRAM module and try to boot the board. If the board now boots up the NVRAM likely needs replaced. If the MPU is still locked up something went wrong during the socket install or the daughter board cracked solder during the nvram socket install.

The FM16W08 works down to 3.3v. The CE combining chip is a 74HCT00D. I haven't run into any situations where the v drop from the battery block diode causes issues.

#30 7 months ago
Quoted from barakandl:

System 80B games will boot up with no 5101 (NV)RAM installed. Remove the NVRAM module and try to boot the board. If the board now boots up the NVRAM likely needs replaced.

Great info! I have the same issue as the OP with my gold wings game. Looking forward to a solution.

#31 7 months ago
Quoted from PinballManiac40:

Have you tested all the pins to adjacent pins on the IC socket to be sure too much solder did not flow thru to the top side shorting out adjacent pins?

Yep, I checked that... there are (3) sets of adjacent pins that should be connected together, the rest not. Good point though, for anyone else, definitely check that.

#32 7 months ago
Quoted from barakandl:

System 80B games will boot up with no 5101 (NV)RAM installed. Remove the NVRAM module and try to boot the board. If the board now boots up the NVRAM likely needs replaced. If the MPU is still locked up something went wrong during the socket install or the daughter board cracked solder during the nvram socket install.
The FM16W08 works down to 3.3v. The CE combining chip is a 74HCT00D. I haven't run into any situations where the v drop from the battery block diode causes issues.

Thanks @barakandl That's good to know, I had no idea. Just checked with nothing in the socket, same issue, so the NVRAM is good (no surprise since the other old RAM chips didn't help either I guess).

So is the next step to pull the board again, and reflow solder to the daughter board connections where they go to the main board? Or should I desolder the daughter board completely from the main board, reflow the underside of the daughter board, then reattach it to the main board? I haven't had daughter board issues with the 80B games I've owned.

#33 7 months ago
Quoted from MaxAsh:

Thanks @barakandl That's good to know, I had no idea. Just checked with nothing in the socket, same issue, so the NVRAM is good (no surprise since the other old RAM chips didn't help either I guess).
So is the next step to pull the board again, and reflow solder to the daughter board connections where they go to the main board? Or should I desolder the daughter board completely from the main board, reflow the underside of the daughter board, then reattach it to the main board? I haven't had daughter board issues with the 80B games I've owned.

Double check around the IC socket install if it stopped working after putting that in. Make sure not traces or holes got torn out and make sure nothing is shorted together that shouldnt be. Like where a trace passes between two IC socket pads.

The daughter board is a pain to rework. You can try to reflow solder but you dont have access to all of the solder joints without removing it entirely which is not the easiest thing to desolder.

#34 7 months ago

I can vouch for Andrews nvram working in System 80b. I've put several in System 80 and 80b (Mars, GoldWings, Hollywood Heat) machines without issue.

#35 7 months ago
Quoted from barakandl:

Double check around the IC socket install if it stopped working after putting that in. Make sure not traces or holes got torn out and make sure nothing is shorted together that shouldnt be. Like where a trace passes between two IC socket pads.
The daughter board is a pain to rework. You can try to reflow solder but you dont have access to all of the solder joints without removing it entirely which is not the easiest thing to desolder.

Okay thanks, I'll check everything again. I didn't think about checking where traces pass by other socket pads, they do sneak between them. Worth checking for shorts on non-adjacent stuff as well.

I guess I need to do my best to try and desolder that daughter board. I have a feeling it will be a huge pain, but if I'm pulling the board again to test, I might as well try. I have a feeling it will be a tough one.

barakandl In terms of trying to fix this... is the replacement board on your site a better option for my situation? Or is the Piggy Deux a better choice? I've never needed a replacement or work around on any System 80B before.

#36 7 months ago

Check out that RAM IC socket thoughly first.

#37 7 months ago
Quoted from MaxAsh:

Okay thanks, I'll check everything again. I didn't think about checking where traces pass by other socket pads, they do sneak between them. Worth checking for shorts on non-adjacent stuff as well.
I guess I need to do my best to try and desolder that daughter board. I have a feeling it will be a huge pain, but if I'm pulling the board again to test, I might as well try. I have a feeling it will be a tough one.
barakandl In terms of trying to fix this... is the replacement board on your site a better option for my situation? Or is the Piggy Deux a better choice? I've never needed a replacement or work around on any System 80B before.

The one I make is a much smaller footprint of the same original circuit. It has posts that will mate with an IC socket if you want. The much smaller foot print should resist cracking more than the original. Whether or not using a dip24 socket is better than hard soldering the daughter board in is probably up to debate.

The Piggy Deux one plugs into the test socket if I remember right. Advantage with that may be you can cut out the original daughter board or maybe even leave it on the board with no EPROM installed and not have to do solder rework that area.

#38 7 months ago
Quoted from PinballManiac40:

Check out that RAM IC socket thoughly first.

Just tested the socket. I checked from every pin to every possible other pin. The only pins that show connectivity between each other are the ones that should:

Z5, Pins
9 & 10
11 & 12
13 & 14
16 & 16

Assuming I'm reading the schematic correctly, that's all as it should be.

#39 7 months ago

Pulled the board, rechecked the socket work, all seems good. Checked out and reflowed the daughter board from behind the CPU. I didn't expect it to change much, and it hasn't.

Anything else you can think I should test? If removing the daughter board is as hard as some people say, should I go for the Piggy Deux workaround board? Or maybe try to find someone local with another 80b and borrow their board just to make sure that's the issue?

#40 7 months ago
Quoted from barakandl:

The CE combining chip is a 74HCT00D. I haven't run into any situations where the v drop from the battery block diode causes issues.

74HCT00 parts are rated for 4.5 to 5.5V operation. At his 4.5V, he's at the very bottom edge of the parts rated VCC range. I would think shorting CR34 would bring the VCC back into proper operating voltage range. Running at the voltage extremes (either high or low) is never a good idea.

74HC00 parts will run at the lower voltage range (2V to 6V) with no problems. And since the two CE inputs are driven by 4000 series CMOS operating from the same Vbat voltage - the 74HC00 would be a much better choice. Food for thought - two FET's and a pullup resistor would have been a good choice as well.

As to the mention of not running without the reset board. Some boards refuse to operate properly without the DIP plug installed regardless of whether or not the reset board is connected. This is due to the addition of a pullup resistor that Gottlieb added during 80A days.
When this resistor is added - some of the boards come back to life.

That_Resistor (resized).jpg
#41 7 months ago
Quoted from G-P-E:

As to the mention of not running without the reset board. Some boards refuse to operate properly without the DIP plug installed regardless of whether or not the reset board is connected. This is due to the addition of a pullup resistor that Gottlieb added during 80A days.
When this resistor is added - some of the boards come back to life.

Tell me more, as I have a unresponsive Raven taking up space in my basement. Which pins, how many ohms, any service bulletin to read?

#42 7 months ago
Quoted from G-P-E:

74HCT00 parts are rated for 4.5 to 5.5V operation. At his 4.5V, he's at the very bottom edge of the parts rated VCC range. I would think shorting CR34 would bring the VCC back into proper operating voltage range. Running at the voltage extremes (either high or low) is never a good idea.
74HC00 parts will run at the lower voltage range (2V to 6V) with no problems. And since the two CE inputs are driven by 4000 series CMOS operating from the same Vbat voltage - the 74HC00 would be a much better choice. Food for thought - two FET's and a pullup resistor would have been a good choice as well.
As to the mention of not running without the reset board. Some boards refuse to operate properly without the DIP plug installed regardless of whether or not the reset board is connected. This is due to the addition of a pullup resistor that Gottlieb added during 80A days.
When this resistor is added - some of the boards come back to life.[quoted image]

I love all this info, thank you.

I left the jumper on CR34, and measured the same pins Z4 pins 7 & 14 = 5.06V (pin 4 also 5.06V). No change, still not booting.

Where to next? Is it possible one of the connectors could be an issue? They probably haven't been taken on/off in at least a decade or two. Would repinning or doing more than cleaning the board edges be a possible fix? Trying to eliminate whatever I can before I start running around buying stuff.

#43 7 months ago
Quoted from G-P-E:

74HCT00 parts are rated for 4.5 to 5.5V operation. At his 4.5V, he's at the very bottom edge of the parts rated VCC range. I would think shorting CR34 would bring the VCC back into proper operating voltage range. Running at the voltage extremes (either high or low) is never a good idea.
74HC00 parts will run at the lower voltage range (2V to 6V) with no problems. And since the two CE inputs are driven by 4000 series CMOS operating from the same Vbat voltage - the 74HC00 would be a much better choice. Food for thought - two FET's and a pullup resistor would have been a good choice as well.
As to the mention of not running without the reset board. Some boards refuse to operate properly without the DIP plug installed regardless of whether or not the reset board is connected. This is due to the addition of a pullup resistor that Gottlieb added during 80A days.
When this resistor is added - some of the boards come back to life.[quoted image]

74HC00 actually caused me problems at times in gottlieb sys 80b where HCT00 worked fine. Testing with a HC00 in my 80B game occasionally the RAM gets scrambled and the high scores would show junk, if you go to ram test it would still pass. I did not have pullup but it should work with 74HC00D. Something odd happens probably power up or down where the RAM corrupts. Tons of 5101 modules all with 74HCT00D and never had any reports about trouble from V drop of the diode. Granted I sell them towards a few specific 5101 systems that I know work but maybe not every possible 5101 application outside of pinball. I guess adding pads for 0805 pullup resistors on the next time I order PCBs wont hurt. Then I can try again with HC00

I did have to put a 10K pullup resistor for /CE on 6116 NVRAM modules destined for Bally Midway arcade games. Without the /CE pullup those games will fail to boot and scramble the RAM at times.

#44 7 months ago
Quoted from GRUMPY:

Tell me more, as I have a unresponsive Raven taking up space in my basement. Which pins, how many ohms, any service bulletin to read?

Don't know when this took effect. But my Ice Fever came with this mod. And there was a slip-in page in the manual describing a 3K resistor -- pulling the read/write* signal (pin 11) to Vcc (pin 7). Of course - I cannot find this page now.

#45 7 months ago

Might be worth investigating why the 74HC00 didn't work. One bad thing is the timing for the Gottlieb circuitry was horribly s-l-o-w. 4000 series parts aren't exactly known for speed. The 74HC00s would add to this so you need to factor that into the timing calculations. I'd hang a scope on there to capture any glitches to see where they would be coming from, that enable must be disabled when power down/up is occuring. Would be better than running the HCT part at the minimum VCC rating.

Or easiest --> just tell people to jumper over CR34 if using this module. Not that this helped the O.P., though.

#46 7 months ago
Quoted from G-P-E:

Or easiest --> just tell people to jumper over CR34 if using this module. Not that this helped the O.P., though.

It's okay, knowledge should still be out there, even if it doesn't help my specific problem

#47 7 months ago
Quoted from MaxAsh:

It's okay, knowledge should still be out there, even if it doesn't help my specific problem

Actually it gives me pause that the System 80 I'm currently working on may NOT have bad ram, but something else going on related to the battery failure and subsequent leakage. When I pull the board to socket the location I'll have to do some continuity and voltage testing.

Regardless of that, I'd rather have NVRAM then a battery pack, even remote mounted.

#48 7 months ago

Anyone near Southern NH want to let me borrow a system 80B board to test?

#49 7 months ago
Quoted from MaxAsh:

Anyone near Southern NH want to let me borrow a system 80B board to test?

If you were closer, I could loan you a complete Hollywood Heat.

20190706_213249_resized_1 (resized).jpg
#50 7 months ago
Quoted from MaxAsh:

If removing the daughter board is as hard as some people say, should I go for the Piggy Deux workaround board? Or maybe try to find someone local with another 80b and borrow their board just to make sure that's the issue?

If you don't have experience with removing the daughter boards on these MPUs, I'd highly suggest either sending your MPU out for repair or if you think the daughter board connections may be at fault you could try the Piggy Deux. It comes down to a time vs. money vs. risk of damaging the MPU further.

The daughter board is not an easy thing to remove/desolder, due to how it's all sandwiched together. You can't easily get under it with cutters to snip it out. The traces are thin on the MPU and pads don't put up with a lot of heat. Through-holes for the 2.54mm headers they used to connect the boards are sized too small so don't easily clear with a desoldering gun. In-short... it's very likely, if you haven't practiced on other boards, that you'll do some damage trying to remove the daughter board. I tried removing a few of these on junk boards years ago and spent a few hours between removal & then having to fix some pads/traces, and that was even with decent equipment and taking my time. Decided there had to be a better solution so people weren't damaging their MPUs (sometimes beyond repair) and that's when I created the Piggy Deux @ https://www.pinitech.com/products/gottlieb_piggydeux.php.

The Piggy Deux is designed as a plug-and-play fix for daughter board issues. You don't remove the original daughter board & there's no soldering involved. Takes just a few minutes to install (recommended you pull the MPU and set on a flat surface, remove the EPROM from the daughterboard, install the Piggy Deux with eprom into TC1). If the board still doesn't boot, then you've got other issues -- and if you can get the board working 100% without the Piggy Deux, you can save it for the next Gottlieb Sys80B.

Where the Piggy Deux could help is if as you press on the daughter board while powering on the game, you sometimes get the game to boot. Or if the game's booted and you press around on the daughter board, it resets or freezes. That usually indicates daughter board solder connection issues. In that case the Piggy Deux is an easy way to fix the issues that will save you a lot of time/frustration.

Considering what's been posted in this thread, the board was working BEFORE the installation of the NVRAM. Any time you have a working board that you make a change to and it stops working, 9 times out of 10 the problem is going to be where the change was made. If you haven't already dumped a lot of time into beeping things out at the 5101 socket, that's where I'd concentrate effort. If there's a small fleck or solder bridge making a connection between two address, data or other signals at the socket, the board won't boot because signals are shorted.

With the NVRAM out of the board, take some close-up pictures of the front and back of the 5101 socket. There might be something someone catches in those pictures that could help you out. Otherwise, if I was you I'd use a meter on continuity test and beep things out at the 5101 socket -- without any RAM in there. Use the schematic to verify connections and check adjacent pins for address/data lines that SHOULD NOT have a connection.

---
http://www.pinitech.com - "Pinball Inspired Technology"
NVRAM, Bally/Stern LED Displays & Mods for pinball machines

Promoted items from the Pinside Marketplace
Wanted
Machine - Wanted
York, PA
Wanted
Machine - Wanted
Bokchito, OK
$ 19.99
Electronics
PinballElectronics.com
$ 299.00
Displays
Boston Pinball Company
From: $ 18.00
Apparel - Men
Pinside Shop
€ 8.40
$ 10.00
Cabinet Parts
Ramp-O-Matic
$ 269.99
$ 48.00
Cabinet - Other
ModFather Pinball Mods
$ 26.99
Lighting - Interactive
Lee's Parts
$ 35.00
Hardware
Filament Printing
$ 27.99
Lighting - Interactive
Lee's Parts
There are 107 posts in this topic. You are on page 1 of 3.

Hey there! Got a moment?

Great to see you're enjoying Pinside! Did you know Pinside is able to run thanks to donations from our visitors? Please donate to Pinside, support the site and get anext to your username to show for it! Donate to Pinside