CodeCell: Read Analog Values with ADC

Analog sensors, potentiometers, and other variable inputs require an Analog-to-Digital Converter (ADC) to be read by a microcontroller. With CodeCell, reading an analog signal is as simple as calling pinADC().

How to Use pinADC()

To read an analog value, use:

uint16_t myADC = myCodeCell.pinADC(uint8_t pin_num);

• pin_num → The ADC pin you want to read from (IO1, IO2, or IO3).
• Returns a 12-bit value between 0 and 4095 (corresponding to 0V – 2.5V, due to the internal voltage reference).

Example: Reading a Potentiometer

If you connect a potentiometer to IO2, you can read its position with:

uint16_t potValue = myCodeCell.pinADC(2);
Serial.println(potValue);

Correct Potentiometer Wiring:

Since the maximum voltage on CodeCell’s ADC pins should not exceed 3.3V, you should connect the potentiometer to 3V3 instead of Vo:

3V3 → One end of the potentiometer  
GND → Other end of the potentiometer  
IO2 → Middle pin of the potentiometer  

Important: Internal Voltage Reference is 2.5V

The onboard microcontroller uses a 2.5V internal voltage reference. This means:

• If your input voltage is 2.5V, the ADC reading will be 4095 (max value) - any voltage above 2.5V will be 4095
• If your input voltage is 1.25V, the ADC reading will be around 2048.
  

To scale readings properly:

float voltage = (myCodeCell.pinADC(2) / 4095.0) * 2.5;
Serial.println(voltage);

Whether you're reading a potentiometer,  sensor, or other analog signals, CodeCell makes ADC reading easy.