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Old 04-16-2014, 02:03 PM   #28 (permalink)
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Originally Posted by P-hack View Post
I considered duty cycle transmission, it is cool stuff, the only issue is that it is another analog link in the chain.
I do not agree. PWM is excellent because it can be seen as both digital (by the MCU and other digital devices) and analog (by a load such as a motor or light).

An analog signal at a specific voltage that receives interference/induced voltages can easily be skewed to a value that is incorrect. That is obviously why digital is superior.

Even if a PWM signal's voltage is skewed by interference, the timing will not change, and the timing is what the pulseIn() command reads to convert the pulse width to an integer value. However, interference will be nearly impossible because the signal will either be low (with a 10K resistor to ground to make sure) or high (+5V applied by MCU). There is no room for interference.

This is how I understand it....but I could be wrong.

I will add more multiplexed inputs tonight. I have 2 temp sensors and 2 5K pots. Maybe I can find more goodies to input.
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