www.96kHz.org
advanced audio recording
DIY MIDI controller
  15
endless
rotary
encoders

1
virtual
input
channel

10 bits
accuracy

1024
steps
resolution

acceleration
option

fine
tuning
option

16 channel MIDI controller
.
DIY MIDI Contoller

15 rotary encoders of ALPS with pushbuttons are included in the box. A Xilinx PLD is used to interpret the movement information and send it over 230kpsp serial interface to the computer or the DIY audio workstation and also PC. The controller data is always 10 bits for 1023 step fine resolution either achieved by 1,2,4 or 8 complete turns of the controller. Intelligent acceleration is used as well as fine adjustment when pressing the knobs.

A virtual channel for pass through is added on MIDI channel 0.


A FPGA ist used to control the data streams:

MIDI Controller with virtual input and 10 bit
 The FPGA can operate the incoming data much quicker if required, but a 750 point per second resolution obtained from the sequential polling seems sufficiant. If desired the transmission speed could be increased up to 920kbaud, but 230kbaud is the limit of most simple UARTs with PCs. See the data protocol options of my improved MIDI for details.

Standard CTRL setp for Synth Control:

DIY MIDI Contoller

DIY MIDI Contoller

A next step is to implement the MIDI over S/PDIF for fast transmission and adaption to the workstation.

See another Version of the MIDI Controller 15


 

 

© Jürgen Schuhmacher 2004