Chain MIC Tutorial

#include "M5Chain.h"

#define RXD_PIN GPIO_NUM_5  // 48 for the other side of Chain DualKey
#define TXD_PIN GPIO_NUM_6  // 47 for the other side of Chain DualKey

Chain M5Chain;

device_info_t devices[8];
device_list_t device_list = {0, devices};
uint16_t device_count = 0;
#define START_KEY_PIN GPIO_NUM_0
#define STOP_KEY_PIN GPIO_NUM_17

uint8_t mic_id = 0;
bool mic_found = false;
bool print_adc = false;
bool start_key_last = HIGH;
bool stop_key_last = HIGH;

void setup() {
  Serial.begin(115200);
  delay(1000);
  Serial.println("===========================");
  Serial.println("M5Stack Chain MIC Test");

  pinMode(START_KEY_PIN, INPUT_PULLUP);
  pinMode(STOP_KEY_PIN, INPUT_PULLUP);

  M5Chain.begin(&Serial2, 115200, RXD_PIN, TXD_PIN);
  while (!M5Chain.isDeviceConnected()) {
    Serial.println("No device connected");
    delay(1000);
  }

  if (M5Chain.getDeviceNum(&device_count) != CHAIN_OK || device_count == 0) {
    Serial.println("Failed to get device count");
    return;
  }
  device_list.count = device_count < 8 ? device_count : 8;
  if (!M5Chain.getDeviceList(&device_list)) {
    Serial.println("Failed to get device list");
    return;
  }

  for (uint16_t i = 0; i < device_list.count; i++) {
    if (device_list.devices[i].device_type == CHAIN_MIC_TYPE_CODE) {
      mic_id = device_list.devices[i].id;
      mic_found = true;
      Serial.printf("ID[%d] is Chain MIC\n", mic_id);
      break;
    }
  }

  if (!mic_found) {
    Serial.println("Chain MIC not found");
    return;
  }

  Serial.println("Press KEY1 to start ADC output");
  Serial.println("Press KEY2 to stop ADC output");
}

void loop() {
  const bool start_key = digitalRead(START_KEY_PIN);
  const bool stop_key = digitalRead(STOP_KEY_PIN);

  if (start_key == LOW && start_key_last == HIGH) {
    print_adc = true;
    Serial.println("ADC_PRINT_START");
  }
  if (stop_key == LOW && stop_key_last == HIGH) {
    print_adc = false;
    Serial.println("ADC_PRINT_STOP");
  }
  start_key_last = start_key;
  stop_key_last = stop_key;

  if (!mic_found || !print_adc) {
    delay(10);
    return;
  }

  uint16_t adc = 0;
  if (M5Chain.getMIC12BitAdc(mic_id, &adc) == CHAIN_OK) {
    Serial.print("MIC ADC=");
    Serial.println(adc);
  } else {
    Serial.println("MIC ADC read failed");
  }
  delay(100);
}