Doepfer Schaltwerk Resources Page
Hello, this is my page dedicated to reworking the Doepfer Schaltwerk into a more useful MIDI sequencer.
Right now I only have a few things here, but I will be adding more as development gets under way.
NEWS
09/16/03 - I am continuing work on the OS
changes... as a teaser I have put up a video of the rotate function in action!
check it out here:
http://www.socialentropy.com/schaltwerk/schalt_rotate2.wmv (it's a
1.3MB WMV file)
here's a picture of the studio while in 8051
programming mode!
and a picture of the back of the schaltwerk with all
the test equipment installed.
01/21/03 - OK, after a long time I have had a few weeks to really work on the OS. I have gotten almost all of the OS parts mapped out and now have enough knowledge of the code to begin adding new features. I have been using a different EPROM emulator (FlexROM II) which greatly sped things up with it's 'address capture' capability.
06/10/02 - I have successfully compiled a simple OS that exercises the buttons, MIDI I/O, LEDs and LCD display. Although it has no practical use yet, this is a big step, because hardware control is out of the way. I also created some initial C structure definitions to include all of the features I want, and it is going to be tough fitting everything into memory. Things multiply quickly with 4banks x 32patterns x 8tracks x 16steps = 16384 just for all the single steps possible!
05/01/02 - I have gotten the development environment set up, here's a picture of the Schaltwerk with the ROM emulator in place.
LINKS
Schaltwerk page on Doepfer website
Retranslated Schaltwerk Manual (MSWord format)
Fictional New Features Documentation (created by me)
Schaltwerk OS v1.31 Binary file
Yahoogroups Schaltwerk mailing list
Yahoogroups Doepfer A100 mailing list (check the archives for some good schaltwerk info, but they get a little touchy talking about the Schalt on there :-) )
Technical Stuff
The Schaltwerk uses an Infineon SAB-80C537 (8051) 8-bit microcontroller.
Newer Schaltwerks have a 1Mbit EPROM for control store (ST MT27C1001 100nS access time). I will be using the EconoROM III EPROM emulator in it's place for development.
Also there is 1Mbit CMOS SRAM (EliteMT LP621024D)
The MIDI circuits use the Motorola CNY17-2 opto-isolator
The buttons and LEDs are controlled using a serial-to-parallel type circuit based on 4094 ICs (example) which allows many LEDS and buttons on a few pins of the 8051.
There are three types of boards in the Schaltwerk:
pictures of internal boards are here.
