The key assigner allows to generate two independent control voltages and gate signals from the time multiplexed data from the keyboard circuit. Each output can be selected between two monophonic, two duophonic and two key-split modes with a fixed split point between key 24 and 25 (see above).

To achieve this, the pulse train from the keyboard is stored in two 64 bit serial shift registers (Texas Instruments TMS3417). Those are controlled using the synchronization signals from the keyboard circuit, the mode switches on the front panel and a circuit defining whether the real time keyboard data or the recirculated output is fed into the registers.
The shit register output, together with additional control signals, are fed to a second PCB which converts the pulses (not parallel digital data!) to the precise control voltages.

A detailed circuit description follows.