Hi, I bought this sensor, connected it and worked perfectly the first time.

Now, it only works in address 39. I see that there are ways to change the address but it seems that the one I bought does not have jumpers for that purpose.

So, my question is: why 39 ? With the other addresses it does not even see the sensor.

OK, after some search I found the answer:

The ADDR pin can be used if you have an i2c address conflict, to change the address. Connect it to ground to set the address to 0x29, connect it to 3.3V (vcc) to se t the address to 0x49 or leave it floating (unconnected) to use address 0x39.


So for more flexilbility we should buy sensors with the ADD pin accessible.

Hey Neiva,

Glad you got the TSL2561 connected with ease! Did you see our tutorials?

Yep, you go it exactly right.

Welcome to the Cayenne community,


The way this application is working with this sensor is detecting the edge triggers. For example, if I want turn on a light whe lux is below 50, than when the sensor goes below 50 than it can trigger an action like activating pin 17 connected to a relay connected to a light. But we need this edge trigger. If the lux is already below 50 the trigger does not execute. So, would it be possible to have the trigger to execute on the level and not on the edge meaning, the usually lazy CPU would have to work and poll the sensor each minute, for example. If the condition is met, lux<50, then the trigger would execute. This is far more powerfull than the edge trigger.

Are there any plans to develop this feature ?

By the way, I am thrilled with the softwae, I was looking for this for some time. Congratulations.