Connecting Color Sensor to Zumu 32u4

Hi There,
I am trying to connect APDS9960 and Adafruit_TCS34725 to Front Sensor Array by wiring them as follows:

pin 2 to SDA
Pin3 to SCL
Pin 4 to V3.3
Square Pin to GND

The color sensors are working but one of the sensors in Front Sensor Array is always high, it value (2000), once I removed the color sensers, the front sensor array works normal.

Is there is any explanation why that is happening?

Pin 4 on the Zumo 32U4 is used for line sensor 4 or the right proximity sensor output (depending on the position of the jumper on the sensor board). It isn’t really clear what you’re trying to do with the connection to pin 4, but if you are trying to power those boards, you should probably be using the 3.3V or 5V pin from the Zumo instead. Both the 3.3V and 5V pins are available at the front expansion area; you can find more details in the “Expansion areas” section of the Zumo 32U4 user’s guide.

If you continue having problems, could you post a wiring diagram as well as pictures of your setup that show all of your connections?


Hi Brandon,
That is right I used pin 4 as a power for these sensors, I modified it and took a power from the Zumo and it works. Thanks a lot.

Do you have the schematic for the line sensor board itself ? I could not find it.


You can find a schematic of the Zumo 32U4 Front Sensor Array on the last page of the “Schematic diagram of the Zumo 32U4 OLED Robot” found under the “Resources” tab of the robot’s product page.

You can also find some information about it in the “Front sensor array” section of the Zumo 32U4 user’s guide, and refer to the front expansion are pinout shown in this diagram from the “Expansion areas” section.