Download filezillafor windows
The same circuit is shown below laid out on the PROTON Development Board
MK2. Capacitors C5 to C7 are used to store a voltage produced by resistors R1 to R3.
Each resistor and capacitor pair form an envelope generator for their respective
channel. Resistors R4 to R6 allow the voltage to modify the output of pins
PORTA.0 to PORTA.2, which in turn are fed to the amplifier via a crude mixer
formed by resistors R7 to R9. When the power is first applied to the circuit or a reset is implemented, each
note will play at once forming a chord, with the sound from PORTA.0 being the
loudest, PORTA.1 having a fraction less volume and PORTA.2 being the lowest
in volume. 100kW LM386 100uF 2.2uF 100nF + + + + - - - -
