I2C Encoder Mini

The I2C Encoder Mini is a small board that allows you to use a rotary encoder with an I2C bus. This can be useful in case you have few GPIOs because the 3 pins allow you to control up to 127 devices. The I2C Encoder Mini will count and store every movement of the encoder, so no need to check the rotary encoder in real-time, the I2C Encoder Mini will do it!

This new version is powered by the ATtiny 402. It has a similar feature to big brother, but it supports only the mechanical encoder (no RGB) and there are no GP pins. The I2C Encoder Mini has pre-soldered the pull-up resistor on the I2C bus. This can be enabled by soldering a jumper.

• I2C bus working up to 400kHz
• Possibility to customize the I2C address with the I2C bus
• It supports the standard rotary encoder
• Open-drain Interrupt output pin, so no need to continuously poll the devices
• 5 pin header 2.54mm pitch on the left and right side, also the JST-XH fit
• 127byte of internal EEPROM
• Voltage range is 3.3V to 5V
• Maximum A/B signal frequency: 100Hz (Tested)
• Dimension of 23x19mm or 0.9×0.74in
• Open source project

There are 4 32bit signed int registers:

• CVAL: Current value of the Encoder. This value changes every time the encoder rotates.
• CMAX: Maximum value that CVAL can reach
• CMIN: Minimum value that CVAL can reach
• ISTEP: How much the CVAL has to increment at each and every encoder step.

• Project
• Arduino Library