Casio CZ/ VZ/ FZ - Pro Series

Hi. I Have a RZ-1 Drum machine and I'm realy like of the sound, but now 
I have a problem with your little memory! The question is: Any knows 
how to do a cable for the Tape Dump?? I NEVER found that strange plug 
or the specs on the web, so I think in any improvisation, but I don't 
know the number of the pins (where's the ground or the positive of 
the "send data" way...) or the right place of then. With some 
information, I do myself the cable and the problems gone! Any answers 
are welcome, please!

Thanks for any help!
P.S.: Anyone see every RZ-1 PLUS ultimaly in some place to sell?? (rs)