Check out this cool synth kit that’s meant to be poked prodded and programmed into whatever you wish. It’s designed by James Grahame of Reflex Audio + Retro Thing, and Peter Kirn of Create Digital Music.
Oscillator A & B slightly detuned, square wave on A and sawtooth on B. FM turned all the way up, distortion on. The filter resonance turned way up (hence the chirpy squeal) and the filter cutoff knob is initially open, then twiddled a bit to help the filter chirp. At the end, I just slowly turn the cutoff down. the VCF envelope modulation is mapped to MIDI velocity, which adds some sonic movement.