Help with an 130XE failed

[Allas]

Another question in XE series. The first row of memories correspond to the main 64K memory, next column is the extended 64 memory. Is possible the XE start up in right way without memories chip in the extended memory column?

 

Someone did that?

[Allas]

Yes, it does. The 130Xe only needs the first column of memory sockets. It can works with only 64K.

 

And a great new, after change a lot of chips I repaired this 130XE. Only remains to add some extra memory chips for the extended memory, but works fine!!

 

It cost me a lot of effort, because I couldn't guess what chips are good and what are bad. I did a multiple combinations. Now i'm going to sleep.

 

Thanks for the good supporting.

[re-atari]

Yes, it does. The 130Xe only needs the first column of memory sockets. It can works with only 64K.

 

And a great new, after change a lot of chips I repaired this 130XE. Only remains to add some extra memory chips for the extended memory, but works fine!!

 

It cost me a lot of effort, because I couldn't guess what chips are good and what are bad. I did a multiple combinations. Now i'm going to sleep.

 

Thanks for the good supporting.

Good job. Persistance always wins

For the record, which steps did you take to get the XE running again? What have you swapped and which component do you suspect to have caused the problem?

 

re-atari

Edited April 18, 2007 by re-atari

[Tezz]

Yes, it does. The 130Xe only needs the first column of memory sockets. It can works with only 64K.

 

And a great new, after change a lot of chips I repaired this 130XE. Only remains to add some extra memory chips for the extended memory, but works fine!!

 

It cost me a lot of effort, because I couldn't guess what chips are good and what are bad. I did a multiple combinations. Now i'm going to sleep.

 

Thanks for the good supporting.

Well done Allas Good to hear another success.

[Allas]

Yes, it does. The 130Xe only needs the first column of memory sockets. It can works with only 64K.

 

And a great new, after change a lot of chips I repaired this 130XE. Only remains to add some extra memory chips for the extended memory, but works fine!!

 

It cost me a lot of effort, because I couldn't guess what chips are good and what are bad. I did a multiple combinations. Now i'm going to sleep.

 

Thanks for the good supporting.

Good job. Persistance always wins

For the record, which steps did you take to get the XE running again? What have you swapped and which component do you suspect to have caused the problem?

 

re-atari

 

Well, I have a 800XL not working because have bad memory chips. Every time I turn on I get directly the test memory program running. The big chips inside my 800XL are socketed. And because of his status of working I supossed ANTIC, 6502, GTIA, PIA and POKEY chips are good, only one pair of memories should be bad.

 

I changed all big chips to my socketed 130XE.

 

I only use left column of memories in 130XE, because represent the main memory. I guessed without the extend memory chips, the 130XE should be as a 65XE.

 

I changed different combinations in the memory until I got the memory test running. After that, I know every replacing, if the chip was bad or good counting the number of bad blocks on screen. Off course I flagged the memory chips as good and bad.

 

Finally I got my 130XE running with 64K. There was 5 bad memories from the total 16. And only i need to buy the extra chips to get my 130XE working with his 128K.

 

Really a socketed machine is a miracle. In the future will be more easy to repair.

[Rybags]

The inbuilt memory test isn't any good for extended RAM - someone's written a comprehensive RAM test that works with most upgrade schemes IIRC.

 

Maybe do a 1 meg SIMM mod instead of putting the old style extended RAM chips back?

[Allas]

<Adm , delete this please>

Edited April 18, 2007 by Allas

[Allas]

I cant find the squematics for 1Mb SIMM mod. But sounds interesting.

 

I forgot to say before, if you change resistances R111 and R110 (at the middle side of memory chips) to cross the connection, you got the extended column chip as a main memory. In this way you could test the memories with the internal test or quickly take a chance to view a problem with damage memory without desoldering.

 

Look at the picture for the trick.