All about the Roland Jupiter-series

What you are calling the memory block is actually the Microprocessor.
I do not have the schematics but they should source the actual part 
number used.
You will need an exact match to that part.
If you have a source of the schematics you should be able to locate the 
processor number.

If you can find the part Roland should be able to install for you.
Also is your version the 12 bit or 14 bit DAC.
The 14 bit DAC have the DCB connection on the back and are known as 
Jupiter 8a.
I'm not sure if they use the same processor again the schematics will 
tell you that.

Dana

Hello,this is a little attachment to my previous email,I think I found 
the
  memory-block on the net...Is this the right one? follow the link
http://en.wikipedia.org/wiki/Zilog_Z80
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