There has been some talk of using the PC-1600 as a CV-->MIDI convertor.  
I did this (and posted the info on how to do it) several months ago on Analogue Heaven. 
Here it is again.  

This worked OK (not great, but hey, what do you want for free?) from 
Prophet 5 --> Microwave.  I had some reports of people saying that it didn't work for 
them, but give it a shot...

----------------------
CV pitch from your synth --> CV1 on PC-1600
CV gate from your synth --> CV2/Footswitch on PC-1600

In UTILITY mode:
  Set Ftsw1 to Btn1

In EDIT mode:
  Set CV1 to "String", and set the following String:  9X pr 7F
(where X = hexadecimal of (MIDI channel of destination synth - 1) and 7F is
arbitrary velocity setting (0 = velocity 0, 7F = velocity 128)

  Set Button 1 to "String prs/rls", and set the following:
    "Press String"   FE
(a dummy message, really an Active Sensing message)

    "Rls String"   BX 7B 00
(where X = hexadecimal of (MIDI channel of destination synth - 1) this is
the "All Notes Off" message)
----------------------

Dan Nigrin
dnigrin@welchlink.welch.jhu.edu

P.S. - Many thanks to John Fera of Peavey, for the suggestion re: using "FE" rather than 
"F1" as the dummy message! (F1 is actually the MIDI Time Code 1/4 frame command).