Adafruit PCF8574 I2C GPIO Expander Breakout
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STEMMA QT / Qwiic breakout for the PCF8574 I2C GPIO expander, adding eight quasi-bidirectional GPIO pins with configurable address jumpers and interrupt output.
STEMMA QT / Qwiic breakout for the PCF8574 I2C GPIO expander, adding eight quasi-bidirectional GPIO pins with configurable address jumpers and interrupt output.
One grouped connection is listed in the table but omitted from the graphic until individual pins are available.
| Pin | Type |
|---|---|
| VIN | Power |
| GND | Ground |
| SCL | I2C |
| SDA | I2C |
| STEMMA QT connectors | I2C |
| P7-P0 | GPIO |
| Expander + | Power |
| Expander - | Ground |
| A0 pin | Unknown |
| A0A1A2 jumpers | Analog, Unknown |
| INT | Signal |
| On LED jumper | Unknown |
One grouped connection is omitted from the graphic until individual pins are available.
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