SunFounder Thales Kit, Manual

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SunFounder Thales Kit for Raspberry Pi Pico, Release 1.0
• RN is the resistance of the NTC thermistor under the rated temperature TN. Here, the numerical value of RN is
10k.
• TK is a Kelvin temperature and the unit is K. Here, the numerical value of TK is 273.15 + degree Celsius.
• TN is a rated Kelvin temperature; the unit is K too. Here, the numerical value of TN is 273.15+25.
• And B(beta), the material constant of NTC thermistor, is also called heat sensitivity index with a numerical
value 3950.
• exp is the abbreviation of exponential, and the base number e is a natural number and equals 2.7 approximately.
Convert this formula TK=1/(ln(RT/RN)/B+1/TN) to get Kelvin temperature that minus 273.15 equals degree Celsius.
This relation is an empirical formula. It is accurate only when the temperature and resistance are within the effective
range.
This code refers to plugging Rt into the formula TK=1/(ln(RT/RN)/B+1/TN) to get Kelvin temperature.
temp = temp - 273.15
Convert Kelvin temperature into centigrade degree.
Fah = Cel
*
1.8 + 32
Convert the centigrade degree into Fahrenheit degree.
print
( 'Celsius: %.2f °C Fahrenheit: %.2f ' % (Cel, Fah))
Print centigrade degree, Fahrenheit degree and their units in the shell.
3.4.14 Light Theremin
Theremin is an electronic musical instrument that does not require physical contact. It produces different tones by
sensing the position of the player’s hand.
The instrument’s controlling section usually consists of two metal antennas that sense the relative position of the
thereminist’s hands and control oscillators for frequency with one hand, and amplitude (volume) with the other. The
electric signals from the theremin are amplified and sent to a loudspeaker.
We cannot reproduce the same instrument through Pico, but we can use photoresistor and passive buzzer to achieve
similar gameplay.
• Theremin - Wikipedia
3.4. Projects 93