Strange iie problem part II

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Strange iie problem part II

This iie is driving me nuts.

Yesterday, I left the iie on for two hours, then I played that game, saved it, then loaded up the same game and all was well.

Today, when I turned on the iie for the first time, the disk drive would not turn on. I switched it off and then back on and it turned on fine.

So, I leave it on for another two hours, played that game again, saved that game, and reloaded the same game and it worked fine.

A few minutes later, I decided to turn the iie on again and it would put "apple //e" twice in the middle of the screen diagonal with each other. I turned it off and turned it on again, it gave me complete garbage on the screen.

After a few more tries to turn it on it turned on. I then turned it off and on a few times and it worked fine, so I left the computer alone.

A few minutes later, I decided to turn the iie on again, and I had problems turning it on again. It is as if the new power supply needs to get hot in order for the computer to work properly.

So, I decided that I should do the iie internal test when it is in this state to see if I get some error codes. I did.

It would display "0000" as it would display the "apple //e" before, twice in the middle of the screen diagonal with each other, then it gave me an error code:

"RAM 10000000"

Now maybe leaving the new power supply on for 2 hours a day was not a good idea or my motherboard really has a ram problem. This new power supply I got was made many years ago but it was new old stock.

Can anyone tell me what the heck this can be?

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Re: Strange iie problem part II

My guess is... RAM error Wink

If your other PSU produced out-of-range voltages on +/-12 V then it is quite possible that the RAM ICs took some damage. What's even worse is that memory failures can have intermittent and/or random behavior. Not sure what the error code itself says, but maybe check the manual and see if it can give you a hint.

I don't think leaving the PSU on for 2 hours is dangerous. They should handle that.

EDIT: just checked this doc: http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Reference/Articles/Apple%20II%20Diagnostic%20Info.pdf

"The 8 chips in the main 64K bank are identified on the screen by the word, RAM followed by eight zeros[...]Any bad RAM chip is shown by a 1 rather than an 0. If the faulty RAM is in the auxiliary 64K bank, the display is preceded by an asterisk"
Looks like "RAM 10000000" really means that you do have a faulty RAM chip then.

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Re: Strange iie problem part II

This new power supply I got was made many years ago but it was new old stock.

So it could have rotted, caps leaked etc. while on the shelf. Put a meter on it and see what its doing.

What revision IIe do you have?

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Re: Strange iie problem part II

This new power supply I got was made many years ago but it was new old stock.

So it could have rotted, caps leaked etc. while on the shelf. Put a meter on it and see what its doing.

What revision IIe do you have?

It's an enhanced iie but it is not a platinum iie. So I guess it's a revision B.

EDIT:

I know now that it is not the power supply. When it started giving me this strange error similar to the ram error, I quickly hooked up another power supply and tested it again. I got the same error.

When I put the cover back on that snaps, the picture changed. So I now know that the motherboard has something loose on it.

So I soldered two of ram chips on the motherboard to make sure that they are secure. I also removed all socketed chips twice and cleaned the pins on the chips on one side with a wire brush and alcohol.

Let's see if this problem appears again.

I did however find this residue on one of the ram chips so I used WD-40 to clean it off the best I could short of desoldering the chip. Maybe the residue came from the chip or maybe it was interfering the proper function of the chip. We shall see.

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Re: Strange iie problem part II

Did you clean the chips on the outside sides or on the inside sides (of the pins)?

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Re: Strange iie problem part II

On the outside. Maybe that was careless, but I did remove them and put them back twice. I thought that doing both sides might have a greater risk of bending the pins and breaking them off, since a wire brush might have a hard time of getting in there. The other reason was that if I wanted to be completely thorough, I would have to touch up every single solder point on both sides of the motherboard. Smile

I will let you guys know what happens. At least I have been able to reproduce that error once a day so it should show up today. And if not today, then definitely tomorrow and the next few days ahead, as I am planning to solve that game from start to finish.

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Re: Strange iie problem part II

No personal slam, but at as a repair tech myself, all I can suggest is to blame yourself first, the hardware 2nd.

Inspect the pins and sockets very closely.
Use a mirror, USB microscope or whatever you have.
It's possible (even likely) that one of the IC pins bent underneath the chip.
It'll look normal from a casual external view, but once you look down the rows of ICs and sockets, you might spot a folded or even broken pin.

You might consider swapping RAM chips if you have them.
I use a handheld chip tester that tests them, but unless you're in Southern California, I'm not loaning it out. Wink

GOOD LUCK!!
K

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Re: Strange iie problem part II

Clean the inside areas. The outside areas do not make contact. Cleaning outside doesn't improve connection conductivity.

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Re: Strange iie problem part II

A wire brush is rather harsh. I may suggest a firm white ink eraser. Or a softer pink pencil eraser, with more effort on your part.

Do one set of chips at a time, like the RAM, and then retest. Then the ROMS, then the MMU IOS CPU. Or whatever groups you feel like.

If you reflow all the connections, be sure and remove the chips from the sockets, or else the heat will allow the IC pins to press the contacts into the plastic socket, and lessen connection pressure - not what you want to do.

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Re: Strange iie problem part II

No personal slam, but at as a repair tech myself, all I can suggest is to blame yourself first, the hardware 2nd.

Inspect the pins and sockets very closely.
Use a mirror, USB microscope or whatever you have.
It's possible (even likely) that one of the IC pins bent underneath the chip.
It'll look normal from a casual external view, but once you look down the rows of ICs and sockets, you might spot a folded or even broken pin.

You might consider swapping RAM chips if you have them.
I use a handheld chip tester that tests them, but unless you're in Southern California, I'm not loaning it out. Wink

GOOD LUCK!!
K

Well, I am one of those people who knows how to fix a lot of things. But by trade, I was a watchmaker. So there is no room for blame for anything or anyone.

There were no broken or folded pins. I am nearsighted so I can see things up close without a need for any magnifying glass or microscope.

Clean the inside areas. The outside areas do not make contact. Cleaning outside doesn't improve connection conductivity.

Where did you get that idea? Isn't it logical to assume that since all chips come with pins bent towards the outside, that they make contact on the outside? In any case, I could not reproduce the problem today, but I cleaned the inside pins anyway, even though they seemed clean before I used the wire brush.

A wire brush is rather harsh. I may suggest a firm white ink eraser. Or a softer pink pencil eraser, with more effort on your part.

Do one set of chips at a time, like the RAM, and then retest. Then the ROMS, then the MMU IOS CPU. Or whatever groups you feel like.

If you reflow all the connections, be sure and remove the chips from the sockets, or else the heat will allow the IC pins to press the contacts into the plastic socket, and lessen connection pressure - not what you want to do.

With the kind of oxidation I saw on the pins, a wire brush was necessary. And no, I won't be reflowing all the connections. I did ALL of the removable chips. I believe I have already fixed this thing. I could not reproduce the error today.

I will be testing this thing for the next few days, I will; let you guys know what happens.

Thanks for the help you guys have given me so far.

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Re: Strange iie problem part II

It is not an "idea". It is how it is. While it might seem "logical to assume", that isn't what's happening here.

The sockets in many classic electronics do indeed make contact with the inner-side of the pins. Lift off a socket body and see for yourself if you don't believe me. If you're not dexterous or skilled enough to do that, then take apart a scrap socket. Whatever..

Chips are mfg with the pins "spread at an angle" for a reason. To to allow forming machines (bending machines) to bend the pins at a variety of selectable angles.

This is done to accommodate different automatic insertion machines and different spacings on the PCB as determined by engineering requirements.

Now, cleaning ICs should never need a wire brush. I mean you're welcome to do so and use a wire brush and scratch/remove the tin plating. It's your stuff.

Understand with a wire brush you get exposed copper (or other alloys) in contact with the socket pin/contact. This means you've got dissimilar metals in contact with each other when you insert the chip. 2, maybe 3, types. And this makes for an electrolysis reaction and oxide buildup when the system is powered. Air moisture, electricity, dissimilar metals, all adds up to no good. Perfect for making a nice insulating oxide layer.

While the system will work for a while, you'll need to repeat the process again and again if you experience intermittent behavior.

I only use a pink eraser, and a white "more abrasive" eraser for the difficult cases. It is also important to clean the socket contacts too. Usually removing and re-inserting a chip is good solution. It scrapes away oxide buildup on the socket contact.

If you're not successful with a pink eraser then you're not "working it" long enough. You will need to clean the eraser by rubbing it on clean paper. Sometimes several times during the course of working a single IC.

I also typically use an anti-oxidant like DeOxit or something similar on the contacts. I use an impossibly thin coating that acts as a sealant and keeps out the oxygen in the atmosphere.

You know that crackling and snapping sound when you pull chips out? It's that oxide layer splitting and shearing. Now you've got debris that gets in the way of the two contacts when you re-insert the chip. In one way it is good because it is a mild abrasive. But best practice says to wipe it off before re-insertion.

Yep. Sounds like minutiae. But it works! And this level of care results in awesome longevity.

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Re: Strange iie problem part II

It is not an "idea". It is how it is. While it might seem "logical to assume", that isn't what's happening here.

The sockets in many classic electronics do indeed make contact with the inner-side of the pins. Lift off a socket body and see for yourself if you don't believe me. If you're not dexterous or skilled enough to do that, then take apart a scrap socket. Whatever..

Chips are mfg with the pins "spread at an angle" for a reason. To to allow forming machines (bending machines) to bend the pins at a variety of selectable angles.

This is done to accommodate different automatic insertion machines and different spacings on the PCB as determined by engineering requirements.

Now, cleaning ICs should never need a wire brush. I mean you're welcome to do so and use a wire brush and scratch/remove the tin plating. It's your stuff.

Understand with a wire brush you get exposed copper (or other alloys) in contact with the socket pin/contact. This means you've got dissimilar metals in contact with each other when you insert the chip. 2, maybe 3, types. And this makes for an electrolysis reaction and oxide buildup when the system is powered. Air moisture, electricity, dissimilar metals, all adds up to no good. Perfect for making a nice insulating oxide layer.

While the system will work for a while, you'll need to repeat the process again and again if you experience intermittent behavior.

I only use a pink eraser, and a white "more abrasive" eraser for the difficult cases. It is also important to clean the socket contacts too. Usually removing and re-inserting a chip is good solution. It scrapes away oxide buildup on the socket contact.

If you're not successful with a pink eraser then you're not "working it" long enough. You will need to clean the eraser by rubbing it on clean paper. Sometimes several times during the course of working a single IC.

I also typically use an anti-oxidant like DeOxit or something similar on the contacts. I use an impossibly thin coating that acts as a sealant and keeps out the oxygen in the atmosphere.

You know that crackling and snapping sound when you pull chips out? It's that oxide layer splitting and shearing. Now you've got debris that gets in the way of the two contacts when you re-insert the chip. In one way it is good because it is a mild abrasive. But best practice says to wipe it off before re-insertion.

Yep. Sounds like minutiae. But it works! And this level of care results in awesome longevity.

I didn't believe you.

So, I took apart a socket and both sides make contact with the pins. Here's something else. Electrolysis can only be done if there is metal in contact with another metal in liquid form. That is not what is happening here. In all of my experience with connections like these, no metal gets "Electrolysis" onto another. I think you are confusing that process with something else called "burnishing".

I have never heard a crackling or snapping sound EVER when I have removed or installed a chip in a socket.

I have a lot of experience with cleaning metals and contacts and I assure you that an eraser would not have done the job with these chips. There was black residue on the pins. When that happens, a wire brush is necessary because that black stuff is oxidation that has become so thick that it must be removed mechanically. To use an eraser hard enough to remove that kind of oxidation would have destroyed or broken off the pins.

The wire brush I used had very thin wires that were strong enough to remove the oxidation but not hard enough to break the pins.

Forgive me, but all my experience and observations and instincts tell me that what you're saying is not entirely how things really are.

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Re: Strange iie problem part II

I think we can all agree it's mainly oxidation. And there has never been any amount of "black stuff" so large that a pink eraser wouldn't do the job.

A wire brush is too harsh on the plating and makes too many scratches in it. Or removes it entirely and exposes copper (if present). I never have to use wire brushes on ICs and small electronics. Car battery contacts? That's a different story..

Just about every IC that's been sitting in a socket for some time will make a high pitched crackle or snapping/squealing sound as the oxidation-cum-adhesive breaks free. Once it gets moving the sound goes away.

Flexing a motherboard full of socketed ICs (which I don't recommend) will make a sound like ice creaking in a forest. It doesn't take teenager-quality ears to hear it either.

I tend to think of burnishing as a mechanical rubbing action that polishes the surface. In fact, that's what happens with the pink eraser. I typically rub the pins a few strokes, then transfer the debris to a piece of paper, and then do it again. The oxidation debris is its own abrasive compound that gets less and less (in quantity) as you progress through cleaning an IC. Get the right motion rolling and you get a laser-reflector finish. That's a good thing! And it's less than a minute per 16-pin IC.

They look new, and stay that way for a long long time. Especially if you use DeOxit compound (or similar cleaner/antioxidant). and I'm talking a small amount. 1 drop per 20 ICs. This stuff likes to crawl all over the surface and thin itself appropriately.

There are many types of sockets and.of course there are ones that grip the IC pin on both sides. And there's some with round holes. And many ZIFsockets grip from the side. And just about everything from Mountain Computer uses the single-sided (inside contacting) sockets. I'll have to look through some of the more common peripheral cards to see (and illustrate to you) what ones are "single-sided".

*IF* I can find what I believe to be a moderately oxidized chip from some junker cards I will clean half with a pink eraser to show how well it all works. All the chips in my systems are really pretty shiny already.

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Re: Strange iie problem part II

Well, It's relative. There are varying levels of things you can use to remove oxidation. It's just that in this case, I thought it best to use a wire brush. If it was simply a slight discoloration on a flat piece of copper then an eraser would be a good choice. Not to mention that there are more than one type of eraser that you can get. The ones to erase pen ink are much more abrasive.

To remove oxidation I have used in the past:

Tarn-x

Brasso

Wire Brush

Erasers

Toothbrush and ajax cleanser

Polishing wheel with red rouge

Varying pieces of metal with varying abrasiveness

sand paper with varying abrasiveness

The list goes on and on.

Suffice it to say that out of all the available options, I believe I chose the right one.

Today will be the last day that this computer will be tested. For the last three days I have been attempting to duplicate the problem and it has not come back so I pretty much believe this computer to be fixed.

EDIT:

Tested it again today, no problems. It has been around 4 days and I cannot reproduce the error I had. It's been gone ever since that procedure I performed so that's what fixed it.

Thus, I consider this iie to be fixed.

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