Like the value changes,but what does the value represent?
What is the unit of the value?
Resistance is inversly proportional to the amount of light fallen onto the ldr. So, I think the values are in Ohm.
The ADC on pin A0 of the Bolt module is a 10-bit ADC meaning it has the ability to detect and convert voltage to 1,024 (2^10) discrete levels.
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Value represents the luminous intensity.
As the light intensity increases, so voltage of analog input pin also increases. The bolt then converts that voltage a 10 bit digital value that varies from 0-1024
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For the LDR, the resistance is inversely proportional to the light intensity experienced by the LDR. As a result of increased intensity, the resistance across the terminals of the LDR increases.
Here we use a potential Divider circuit, It has two resistors ( 1 LDR and one normal) connected across constant voltage between 0 -3.3V. As the light intensity increases, the voltage drop across the LDR decreases. To balance this drop, the voltage across the normal resistor increases and is measured by the A0 pin. ( the 10k ohm resistor has been connected between ground and A0).
The A0 pin in the bolt Wifi module, to which the LDR is connected, is a 10 bit ADC pin. It means it can show 2^10 (1024) values ie. from 0 - 1023. So it converts the analog value of the voltage to a digital value between 0-1023.
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