Step Sequencer MIDI Generator

Note Sequence: Enter notes in the format: NoteOrMidi:P#:L#:V# (e.g., E3:P1:L2:V110 or 60:P1:L2:V110).
P: Position (step), L: Length (steps), V: Velocity (1-127)
At the end, add | S[steps]:SPB[bars]:BPM[tempo] (e.g., | S256:SPB16:BPM120) to set total steps, bars, and tempo.
If not provided, defaults are 16 steps, 4 bars, and 120 BPM.