Wallace Venable asks about the MIDI specification for German automatic
accordions and concertinas.  Details of those made by Thueringer
Musikantenschmiede can be found here:

  http://www.ziehorgel.de/service_en.php 

It is in German, but much of it is obvious, and I am sure the people
at Thueringer would be please to offer additional advice to an
arranger.  Unfortunately, the rest of their usually excellent web site
is currently "under construction".

Merry Christmas and Happy New Year from the UK,

John Farmer
http://www.musicanic.com/