The VIDAC has one DAC Bus which can be connected to hardware terminal to update the DAC value.
It is possible to multiplex the hardware terminals to this single DAC Bus (of 8-bits).
Can you please provide more info on how / why you want to use more DAC Bus?
Im working on my algoritmic and modular syntesizer - some modules required mcu code some verilog and analog. For better interconnect analog and verilog component require 2 independent verilog to DAC bus (example chua oscillator axis x nad y = 2 bus).
I didn't clearly understand your implementation.
If there are more than one blocks which needs to drive the DAC, then Digital Multiplexer can be used to route a specific component's value to the DAC.
If CPU needs to write into the DAC, then a control register can write into the DAC which inturn is connected via a Digital Mux. The digital multiplexer's select lines can be controlled via hardware signals.