The default I2C address is 0x32.

Power Pins

• VIN - this is the power pin. To power the board, give it the same power as the logic level of your microcontroller - e.g. for a 5V micro like Arduino, use 5V.
• GND - common ground for power and logic.

I2C Logic Pins

• SCL - I2C clock pin, connect to your microcontroller's I2C clock line. This pin can use 3-5V logic, and there's a 10K pullup on this pin.
• SDA - I2C data pin, connect to your microcontroller's I2C data line. This pin can use 3-5V logic, and there's a 10K pullup on this pin.
• STEMMA QT - These connectors allow you to connect to to dev boards with STEMMA QT (Qwiic) connectors or to other things with various associated accessories.

Other Pins

• OUT - This is the output pin from the S-35710. When the S-35710 is actively counting, the pin is high. When the count matches the timer register, the pin goes low. One thing to note, is that on power-up OUT is default low, which means it's not good for a low-power sleep manager, only for watch-dog-like timings.
• !RST - This is the reset pin. If this pin is pulled low, it will reset the timer.

Output Inverter Switch

At the top of the board is a slide switch. This switch determines whether the OUT pin is the default open-drain (high when counting, low otherwise) or open-collector (low when counting, high otherwise).

To keep the OUT as the default, select NOR on the switch for normal. To change the OUT to inverted (still open-drain), select INV for inverted on the switch.

I2C Pullup Jumpers

On the back of the board are three connected jumper pads labeled Pullups on the board silk. These jumpers connect the 10K pullups to the SDA and SCL lines. Cut these jumpers if you want to disconnect the 10K pullups from the I2C clock and data pins.

Power LED and LED Jumper

Output LED and LED Jumper