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initialize pwm frequency
with me kit lm3s6965 board.
i read io.c file in that one line is
Intialize the PWM frequency and duty cycle. g_ulFrequency = 440; g_ulDutyCycle = 50;
what is unit of frequency?why this==440?
I'm guessing that 440Hz is chosen because it's the frequency that's the basis for tuning musical instruments.
i have one doubt regarding to the program of obtaining the inter temp of processor,using the ADC.
In that program i have no any idea how this formula comes?
ulTemp_ValueC = (((1475 * 1023) - (2250 * ulADC0_Value)) / 10230)
Once again thanks for your quick reply.
The formula you are referring to was derived from the conversion formula below (which can be found in the datasheet):
SENSO = 2.7 - ((T + 55) / 75)
Here "SENSO" is the output voltage of the internal temperature sensor, and "T" is the actual temperature reading. Given that the internal reference of the ADC is 3.0 V, and a full scale reading corresponds to an ADC output of 1023, you can use the formula from the example code to convert ADC sample values directly to temperatures.
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