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Pseudo Random Sequencer - 2 Oscillator

Control layout

The red Xs are what was removed and put into its own circuit, the PRNG sequencer.
The holes for the old switches are now filled with red jewels.


Sample 1 5.39 Mb
Sample 2 5.21 Mb
Sample 3 3.78 Mb

Block Diagram

Circuit Function and Description
     This is a Pseudo Random Sequencer with two oscillators.
     This circuit utilizes a 2 to 4 decode. The decode has 4 outputs, 2 inputs, and an enable. When the enable is LOW the outputs will be 1 LOW and 3 HIGH. Which of the 4 is LOW depends on the states of the 2 inputs.
     The 3rd osc controls the enable and sets the tempo.
     To allow more control, if desired, a latch was added to the circuit with 2 switches. The switches connect the decode inputs to either the latch output or latch input. The latch is also connected to the 3rd osc, and will latch on rising CLK edge. When the latch output is fed to the decode the decode outputs will change only once. When the latch inputs are fed to the decode inputs the decode outputs may change with any input changes.
     Dual osc, simply has 2 osc. In phase/sync will toggle 2 sounds/triggers due to the constantly alternating 101010 it is weighted, unlike the PRNG sequencer. Out of phase/sync will trigger all sounds eventually.
     The outputs are constantly changing 010101010101 on both osc, so it is a matter of the intersection of these outputs at the time osc 3 is enabling the decode.

The circuit plugged into the seq is the interface that was also used on the V-tech laptop seq.

This is to illustrate the timing variations of the three osc.
The latch will latch on a rising edge and hold those values until the next rising edge.
Decode is enabled during LOW sig, so a latch sig from a previous rising edge is passed to decode.
If latch is bypassed any state changes go straight to the decode when enable low. These state changes will change triggered sounds. The top two example sig show a constant frequency for each, but they could be like the bottom two examples with varying freq. There is still alternating 10101010.