I am experimenting with a RCWL-0516 Doppler radar motion detector. On the miniboard is a connector ‘CDS’ and one of the breakout pins is labeled ‘CDS’ (circled with red in the picture).
My impression is that the meaning of the CDS connector is to solder here a light-sensitive resistor to switch the device on during dark conditions (a day-night activity suppressing switch).
Before trying to reinvent the ‘CDS’ wheel I have two questions whose answers maybe are on hand in the sensor community:
–- what range of resistor value photoresistor would be supported by CDS?
–- I guess that the CDS pin is set HIGH at a given resistor value (corresponding with light level). Another guess is that pin CDS provides an analog signal depending on the state of teh cds connection (corersponding with light levels).
Anyone around with experience in this respect that would provide some comment, and if possible a snippet of code, please, would be great!