En este video-tutorial, explico cómo utilizar los ADCs (conversor analógico a digital) de 12 bits del ESP32, en
cualquiera de los 18 pines disponibles, desde la IDE de Arduino.
Código Fuente:
void setup() { Serial.begin(115200); /* * Get ADC value for pin * */ //analogRead(36); /* * Set the resolution of analogRead return values. Default is 12 bits (range from 0 to 4096). * If between 9 and 12, it will equal the set hardware resolution, else value will be shifted. * Range is 1 - 16 * * Note: compatibility with Arduino SAM */ //analogReadResolution(12); /* * Sets the sample bits and read resolution * Default is 12bit (0 - 4095) * Range is 9 - 12 * */ analogSetWidth(12); /* * Set number of cycles per sample * Default is 8 and seems to do well * Range is 1 - 255 * */ analogSetCycles(8); /* * Set number of samples in the range. * Default is 1 * Range is 1 - 255 * This setting splits the range into * "samples" pieces, which could look * like the sensitivity has been multiplied * that many times * */ analogSetSamples(1); /* * Set the divider for the ADC clock. * Default is 1 * Range is 1 - 255 * */ analogSetClockDiv(1); /* * Set the attenuation for all channels * Default is 11db * */ analogSetAttenuation(ADC_11db); //ADC_0db, ADC_2_5db, ADC_6db, ADC_11db /* * Set the attenuation for particular pin * Default is 11db * */ analogSetPinAttenuation(36, ADC_0db); //ADC_0db, ADC_2_5db, ADC_6db, ADC_11db /* * Get value for HALL sensor (without LNA) * connected to pins 36(SVP) and 39(SVN) * */ //hallRead(); /* * Non-Blocking API (almost) * * Note: ADC conversion can run only for single pin at a time. * That means that if you want to run ADC on two pins on the same bus, * you need to run them one after another. Probably the best use would be * to start conversion on both buses in parallel. * */ /* * Attach pin to ADC (will also clear any other analog mode that could be on) * */ adcAttachPin(36); /* * Start ADC conversion on attached pin's bus * */ adcStart(36); /* * Check if conversion on the pin's ADC bus is currently running * */ //adcBusy(uint8_t pin); /* * Get the result of the conversion (will wait if it have not finished) * */ //adcEnd(uint8_t pin); /** * When VDD_A is 3.3V: * * - 0dB attenuaton (ADC_ATTEN_DB_0) gives full-scale voltage 1.1V * - 2.5dB attenuation (ADC_ATTEN_DB_2_5) gives full-scale voltage 1.5V * - 6dB attenuation (ADC_ATTEN_DB_6) gives full-scale voltage 2.2V * - 11dB attenuation (ADC_ATTEN_DB_11) gives full-scale voltage 3.9V (see note below) * * @note The full-scale voltage is the voltage corresponding to a maximum reading (depending on ADC1 configured * bit width, this value is: 4095 for 12-bits, 2047 for 11-bits, 1023 for 10-bits, 511 for 9 bits.) * * @note At 11dB attenuation the maximum voltage is limited by VDD_A, not the full scale voltage. */ } void loop() { Serial.println(analogRead(36)); //VP delay(1000); }
