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NEW PRODUCT – Adafruit GPIO Expander Bonnet – 16 Additional I/O over I2C « Adafruit Industries – Makers, hackers, artists, designers and engineers!
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Interfacing an I2C GPIO expander (MCP23017) to the Raspberry Pi using C++ (SYSFS) « Adafruit Industries – Makers, hackers, artists, designers and engineers!
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Amazon.com: Waveshare Evaluation Kit (Type B) Compatible with Raspberry Pi Pico Includes Pico + Color LCD + IMU Sensor + GPIO Expander Comes with Demo Code for GPIO, PWM, I2C, SPI (8 Items) : Electronics
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Adafruit GPIO Expander Bonnet - 16 Additional I/O over I2C [STEMMA QT / Qwiic] : ID 4132 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits
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Adafruit MCP23017 I2C GPIO Expander Breakout [STEMMA QT / Qwiic] : ID 5346 : $5.95 : Adafruit Industries, Unique & fun DIY electronics and kits
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DIN Rail Mount MCP23017 32-Channel GPIO Expander with I2C Interface for Arduino Raspberry Pi, 3.3V/5V Power - AliExpress
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