Microcontroller

Digital Input to Microcontroller

Most microcontrollers run on either 3.3V or 5V logic, whereas Eurorack gates and triggers are usually between 5-8V.
Thus, if you would like to ‘read’ a digital input such as a gate or external clock source from your microcontroller, you will need some method of conditioning the incoming voltage to prevent it from damaging the chip.

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CV Input to Microcontroller

Many digital modules will need at least one CV input, however you have likely noticed that while Eurorack can have ±12V travelling through its patch cables, most microcontrollers will be very unhappy to receive anything outside of the range 0-3.3V. To allow you to ‘read’ the whole 12V CV range, you need to perform something called ‘signal conditioning’. This means that you want to ‘condition’ the potential range of ±12V into 0-3.3V, cutting out any parts you don’t need to read, and scaling the parts that you do to the readable range.

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