The Benjolin has a chaotic sound core. It comprises of two VCOs (each with pulse and triangle outputs), a Rungler circuit, a comparator and a multimode filter.
The Rungler is an eight-step shift register deriving it's input signal from one VCO and it's clock signal from the other VCO. A primitive AD-converter (a XOR logic circuit) converts the Rungler's digital outputs to a staircase voltage which plays the VCOs in an aleatoric way. The Rungler can modulate the cutoff frequency as well.
The oscillators' frequencies can be modulated by CVs as well but the CV inputs are also normalized to the triangle output of the other VCO, easily you can cross-modulate the VCOs when nothing is patched. The Cutoff-Frequency os the filter is normalized to the traingle output of VCO B. A comparator takes the triangle waves and compares them, resulting in a pulse wave form.