Calibration

Here's how the calibration works :

• Flash the airboxlab with a calibration firmware (no wifi, calibration enable, debug calib and debug info sensor)
• Open a serial port, then press c
• You'll be ask what delay you want between each reading, enter the value in ms

#!c
Please enter the delay between readings (in ms) : 
10000

• Choose the type of calibration you want, press 1 for PM, 2 for the temperature or 3 for the humidity

#!c

Please enter the delay between readings (in ms) : 
20000
Please chose the calibration type (1 for PM, 2 for temperature, 3 for Humidity) 
122093, 450, 327643, 986 ,0, 0, 0, 0, 0, 671, 671, 2547, 2547, 4309 ,4309

• You just have to wait two times the delay you type. Each time a line is written in the terminal with sensors value, it means that a reading occured.
• Once all three readings are done, type the value you got : Value_at_0;Value_first_reading;Value_second_reading then press enter

#!c

Please enter the delay between readings (in ms) : 
10000
Please chose the calibration type (1 for PM, 2 for temperature, 3 for Humidity) 
377291, 450, 318535, 888 ,0, 0, 0, 0, 0, 678, 678, 2778, 2778, 5796 ,5796

• It will calculate each a & b, display it (a x 100 & b x 1000) and also display the third value not use in calculus to ensure that you choose the best value.

#!c

Please enter the delay between readings (in ms) : 
10000
Please chose the calibration type (1 for PM, 2 for temperature, 3 for Humidity) 
377291, 450, 318535, 888 ,0, 0, 0, 0, 0, 678, 678, 2778, 2778, 5796 ,5796
388978, 450, 229400, 941 ,0, 0, 0, 0, 0, 679, 679, 2822, 2822, 6105 ,6105
400664, 450, 233426, 946 ,0, 0, 0, 0, 0, 679, 679, 2857, 2857, 6351 ,6351
T_0 : 2778, T_5 : 2822, T_10 : 2857 
Enter the reference values (ref_0;ref_5;ref_10) : 
2780;2825;2860
 0-10   a       : 101 , b : -2557       , Calibrated_t_5         : 2825 
 0-5    a       : 102 , b : -5343       , Calibrated_t_10        : 2861  
 5-10   a       : 100 , b : 300 , Calibrated_t_0         : 2781  

• Choose which coefficient couple you want by pressing 1,2,3 or press 0 to quit the calibration without saving. If you made a mistake entering the value, press -, it will go back to this state.

#!c

Please enter the delay between readings (in ms) : 
10000
Please chose the calibration type (1 for PM, 2 for temperature, 3 for Humidity) 
377291, 450, 318535, 888 ,0, 0, 0, 0, 0, 678, 678, 2778, 2778, 5796 ,5796
388978, 450, 229400, 941 ,0, 0, 0, 0, 0, 679, 679, 2822, 2822, 6105 ,6105
400664, 450, 233426, 946 ,0, 0, 0, 0, 0, 679, 679, 2857, 2857, 6351 ,6351
T_0 : 2778, T_5 : 2822, T_10 : 2857 
Enter the reference values (ref_0;ref_5;ref_10) : 
2780;2825;2860
 0-10   a       : 101 , b : -2557       , Calibrated_t_5         : 2825 
 0-5    a       : 102 , b : -5343       , Calibrated_t_10        : 2861  
 5-10   a       : 100 , b : 300 , Calibrated_t_0         : 2781  
Press 1, 2, 3 to save the corresponding coefficient. Press 0 to skip saving.
Coefficients saved

• You're done, the calibration process is finished, you can see the calibrated value on the debug output via serial.

#!c

706879, VOC, VOC_RAW, CO2, VZ87_VOC, VZ87_CO2, SENSOR_1, SENSOR_2 PM*100, PM_Cal*100,TMP*100,PMP_Cal*100, HUM*100, HUM_Cal*100
707055, 450, 328760, 882 ,0, 0, 0, 0, 0, 672, 672, 3036, 3047, 3778 ,3778
712067, 450, 330633, 879 ,0, 0, 0, 0, 0, 690, 690, 3055, 3066, 3726 ,3726