Apple IIe Enhanced RAM Error Help!

[Mr. Macintosh]

Hi there! I was wondering if anyone could help me with this particularly pesky problem of mine:

So I just recently got an Apple //e off of eBay and was super excited as it came with loads of software and stuff. After cosmetically cleaning it I decided to test and see if the Duodisk it came with worked. I hooked everything up, the computer made a startup beep and the Duodisk did it's clacky thing and the drive indicator light came on. After cleaning the Duodisk I inserted a ProDos floppy into the drive. The computer then displayed the ProDos splash screen and then went to "Relocation/Configuration Error" and the drive turned off.

I ran a self test (solid apple + control + reset) and I was met with a message saying "RAM 00000001"

I repeated this process several times, and the result is always the same. I am assuming this means one of the RAM chips is broken, but I have no idea which one.

If anyone could help me get this computer up and running I'd greatly appreciate it!

 

[uniserver]

if there is a 64k / 80 column card try pulling that first then see if it still does it.

 

[Mr. Macintosh]

I've pulled all cards and it still says the exact same thing every time.

 

[volvo242gt]

Ok, so, yeah, it's a motherboard issue. I'd examine the RAM chips and see if any look suspect... AFAIK, the 4164 chips may still be available new.

-J

 

[dorkbert]

if you get lucky, the RAM is socketed, so just pull it and replace. If it's soldered... well, it could get painful.

 

[Mr. Macintosh]

I've thoroughly looked at all the RAM chips and even cleaned them a little with some alcohol and scrubbing. It doesn't seem like any of them are suspect cosmetically. And yeah, they are all soldered...

 

[Mr. Macintosh]

What would really help at this point I guess is to find out which RAM chip (f6-f13 I think) the "RAM 00000001" error is referring to.

 

[Macdrone]

If you buy one chip you can "piggy back" it one chip at a time and test and the problem should go away then you can replace.

 

[Mr. Macintosh]

That sounds like a really cool idea! I have an Applied Engineering RAMWORKS III that came with the computer, it's all socketed so could I pull a chip from there to test with? Also, how exactly do you "piggy back?"

 

[dorkbert]

I think the RAMWorks card uses 41256s. Do you have a stock 64k Aux RAM card lying around with socketed RAM?

 

[uniserver]

does that piggybacking acutely work?

 

[Mr. Macintosh]

It looks like my RAM chips are 4264, while my RAMWORKS card has all 6342s.

 

[Macdrone]

I checked one 128 upgrade and it worked, I'm sure the IIe should also. Or at least cause a different issue on the correct bad chip.

 

[Mr. Macintosh]

I think I might try piggybacking a 4265 once I can get my hands on one. Can a 4165 replace a 4265?

 

[dorkbert]

they're all variations of 4164 (64kb x 1) ram chip.

 

[Mr. Macintosh]

So are you saying I can piggyback one of my 6342s on one of the 4264s?

 

[dorkbert]

So are you saying I can piggyback one of my 6342s on one of the 4264s?

actually, I've never seen or heard of a 6342 (nor can I find a datasheet for it.) so at the risk of offending, are you sure you read the numbers correctly?

 

[Mr. Macintosh]

Haha no worries, I'm probably wrong. Here is a picture of the RAM on the cards.

 

[volvo242gt]

Those would be 41256 chips.

-J