2020年11月8日 · I am designing a zero crossing detector for Arduino using the 4N35 optocoupler. This is just a small part of a large project. I haven't bought the components yet, so do not ask me for readings. Everything is in the planning phase now. My input will be a 6-0-6 transformer (220V to 6V step down)...

2020年12月25日 · How does Arduino detect zero crossings and non-uniform spikes in interrupt signals? Arduino can use its built-in analog-to-digital converter (ADC) to measure the voltage of the signal at specific intervals. By comparing the voltage values at these intervals, it can detect zero crossings and non-uniform spikes in the interrupt signal.

2020年12月20日 · The above plot has interesting characteristics — it has a periodic pattern. The spikes almost always go below 300 (< 1.24V, LOW for arduino digital logic) from > 900 (> 4.41V, HIGH for Arduino digital logic), so these are the interrupts I want to see. This implies that the optocoupler is working fine, but Arduino still does not call the ISR.

2022年8月13日 · The pins on the Arduino board. You use these pin numbers directly in the Arduino sketch, like digital pin 13 or analog pin A2. The pins of the onboard microcontroller. These are connected to the various pins on the Arduino board, but the mapping differs from one Arduino board to another.

2022年7月27日 · I was searching for a way to measure the remaining charge of a battery using Arduino. Most (almost all) of the tutorials are simply measuring the battery voltage using the ADC on the Arduino. The calculations are pretty straightforward after that — ##5 V## is mapped to ##1023## and ##0## is mapped to ##0## by the ADC.

2018年12月10日 · If you run out of outputs on your arduino I suppose you could "tack on" some shift registers and expand the number of controlled lights indefinitely. You'll lose a few arduino outputs to drive the shift register clocking, etc., but you add 8 outputs with each shift register chip, and they can all share the common functions like clocking and reset.

2022年1月7日 · I'm going to be adding an IR LED to my Arduino Uno and I'm trying to wrap my head around the math used to figure out the exact resistor values needed to use a PN2222A transistor to drive the LED.I know my LED has a voltage drop of 1.35V and I want to run it at 100mA and that I'll be supplying it with 5V from the Arduino. What I don't understand ...

2017年2月9日 · Homework Statement Two pairs of charges are shown in Figure 1. Homework EquationsThe Attempt at a Solution I originally thought that the electric field past point 7 (i.e. points 8,9, 10) was the solution. However, this is wrong. I then considered point 1, yet that was wrong too. I even...

2025年1月16日 · I also used hand dropping as my release method but have since converted to an Arduino controlled pair of solenoids that hold a piece of fishing line attached to the back of the free fall object. When I turn off the solenoids with my cellphone over bluetooth it initiates the drop. Any help with getting the acceleration plot fixed would be ...

2014年10月2日 · As stated in the problem, the distance between two charges is 1.2 m, and you know that there is a point somewhere in between these two where electric field is zero. Imagine that point is p, as is (x) m away from -2 mC charge and (1.2 - x) m away from -3 mC charge. it would look like sth like this: -2mC ----- P ----- -3mc