I am not sure which analog pin (A0, A1, A2…etc) should I use or does it not matter?.

Please see attached code for what I have so far. That being said, I am a beginner at this and I am really just taking part of codes developed by other people online and modifying it. I believe that I need to use interrupts to manually make analog to digital conversions at the same time as I control the servo. I have used analogRead() in a for loop after every degree of rotation but it slowed down my servo and I didn’t get the sampling rate that I need…so analogRead() isn’t sufficient for me. This means that I need continuous analog reading, hopefully multiple current readings (samples) per degree of rotation. I am implementing this by controlling the servo, while reading the current values using a current sensor (1 amp per 1 volt), and reading it in one of the analog pins (i.e. I want to make a feedback where if the servo’s current increase, I would be able control the servo in a different direction or so. The input impedance of this circuit is about 22 kilohms, and the time of conversion - less than 300 ns.So I have a project where I am using an Arduino Uno to control a servo. One of the possible approaches to construct this device is shown in Figure 2. If the required accuracy of analog to digital conversion does not exceed four bits, then as the basis for the ADC can be used quad CMOS logic elements 'NAND' or 'NOR'. Most of the modern op amps is satisfied for these requirements, the inverting inputs of this op amps should be connected to the Vcc/2 (half of power supply voltage). In addition, the comparator must have a high input and low output impedance. Input voltage which can range from zero up to power supply voltage (Vcc) converts to parallel additional binary code at the outputs of the converter.įor normal operation of the ADC requires that the inverter-comparators A1-A4 should be able to switch when the voltage on their inputs equal to Vcc/2 and an error must be no more than Vcc/(2 n-2) (n - number of bits of binary code at output), and the output voltage of the comparator in on/off states should be close to zero and to the Vcc.

The simplest Analog to Digital Converter (ADC) can be constructed as shown in Figure 1.

Analog to digital converter program