The File Save and Load commands work only on the current voice. It is not possible to save settings for all four voices in one file. This limitation will be removed in a future build. A timer is used to drive two counters and a single 31-stage shift register. A parity generator determines the shift register input.
Interval logic translates a four bit value to a note number.
Windows Multimedia API calls are used to send MIDI messages and wave data to available devices. Simple wave rendering converts a note number to a square wave at the correct pitch. A single Windows Timer resource is used to generate timer messages. The timer interval is set from the Tempo slider. The Tempo is variable from 12 to 600 beats per minute.