Multiple REV Color Sensors using an I2C Multiplexer (Java)

[Delaminer]

Hi everybody,
I have seen a lot of posts asking about how to use multiple REV color sensors (v3), but many of them were left unanswered, and so I have made my own solution (in Java).
In order to use multiple sensors on a multiplexer (I am using an Adafruit TCA9548A), all you have to do is create an I2C object with an address of the multiplexer (for Adafruit, it’s 0x70), and write 1 << x, where x is the port on the multiplexer (usually from 0-7).
In code, a simple solution:

//Put this in initialization, like robotInit()
int leftPort = 3;
int rightPort = 7;
I2C multiplexer = new I2C(I2C.Port.kOnboard, 0x70);
multiplexer.write(0x70, 1 << leftPort);
ColorSensorV3 leftSensor = new ColorSensor(I2C.Port.kOnboard);
multiplexer.write(0x70, 1 << rightPort);
ColorSensorV3 rightSensor = new ColorSensor(I2C.Port.kOnboard);

//Run this periodically, like in robotPeriodic()
multiplexer.write(0x70, 1 << leftPort);
int distance = leftSensor.getProximity();
multiplexer.write(0x70, 1 << rightSensor);
Color color = rightSensor.getColor();

Or you could use this handy little class MultiplexedColorSensor (found here), which acts like a wrapper around the color sensor which automatically writes to a common multiplexer before accessing the sensor. You can add the class to your project, and use it like a normal color sensor:

//Put this in initialization, like robotInit()
MultiplexedColorSensor leftSensor = new MultiplexedColorSensor(I2C.Port.kOnboard, 3);
MultiplexedColorSensor leftSensor = new MultiplexedColorSensor(I2C.Port.kOnboard, 7);

//Run this periodically, like in robotPeriodic()
int distance = leftSensor.getProximity();
Color color = rightSensor.getColor();

I hope this helps!

[DrRoboto]

I used this code for distance sensors but after printing the distance, both sensors gave he same exact reading despite being pointed at very different distances

[Delaminer]

Which multiplexer are you using? It might use a different system for changing ports. If it’s also an Adafruit, try changing ports? Are you using the MultiplexedColorSensor class?

[DrRoboto]

It seems to be an Adafruit clone, I linked it in the original post. It’s a distance sensor so I can’t use that class. I’m running into an issue where it can’t seem to keep up with the commands fast enough to change the port so it gives the wrong values