& pcb ...
The MCV32 cpu is a PIC 16F877(A)at 20MHz with a DAC08302 ( 0830,0831..).The referenbce voltage is provided by a TL431 , adjustable from 5 to 12.5V ... Two 4067 are used for the 32 voices analog multiplex stage who drive the same number of S&Hs . Hi quality capacitors are required for S&H stages...
Free PIC ports available are wired to many utility devices like. The basic setup of recognised devices depends of the firmware version.
MCV32 Interface Schematic (pdf)