System Value

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The Master controller is using system values for temperature, humidity and brightness. All values stored for example in eeprom are in system value format. Below you can find the formulas to change system value in to real value.

When Basic Actions and IF THEN ELSE functionality is applied, system values are used.

Temperature

Temperature (°C) is calculated using the following formula:

temperature = (system value / 2) – 32

To calculate the value used in the system (system value), use the following formula:

system value = (temperature + 32) * 2

Temperature is stored in the system in the following way:

System value Temperature (°C)
255 Sensor not connected
254 95
239 87.5
189 62.5
114 25
64 0
63 -0.5
62 -1
58 -3
28 -18
0 -32

Humidity

Humidity is stored in the Master in the following way:

System value Humidity (%RH)
255 Sensor not connected
200 100
190 95
150 75
99 49.5
50 25
10 5
0 0

Brightness

The brightness values are ranging from 0 to 254:

  • 0: Maximum light intensity
  • 254: Minimum light intensity (completely dark)
  • 255: Sensor not connected

Time

The time in eeprom is being written in a special format which fit in 1 byte:

Time -> Special time format that fits in 1 byte:

  • 00h00 -> 0
  • 00h10 -> 1
  • 00h20 -> 2

...

  • 01h00 -> 6

...

  • 12h00 -> 72

...

  • 23h50 -> 143
  • 23h50 -> 144

Special time format >144 will be ignored.