ESP-OBD2-CAN-Receive.ino

#include "driver/gpio.h"
#include "driver/twai.h"

void setup() {
  Serial.begin(115200);

  twai_general_config_t g_config = { // สร้างต้วแปร g_config ใช้กำหนดค่าเกี่ยวกับบัส CAN
    .mode = TWAI_MODE_NORMAL,
    .tx_io = GPIO_NUM_26, // กำหนดขา TX ต่อกับ 26
    .rx_io = GPIO_NUM_27, // กำหนดขา TX ต่อกับ 27
    .clkout_io = ((gpio_num_t) - 1),
    .bus_off_io = ((gpio_num_t) - 1),
    .tx_queue_len = 5,
    .rx_queue_len = 5,
    .alerts_enabled = TWAI_ALERT_NONE,
    .clkout_divider = 0
  };
  twai_timing_config_t t_config = TWAI_TIMING_CONFIG_500KBITS();
  twai_filter_config_t f_config = TWAI_FILTER_CONFIG_ACCEPT_ALL();

  if (twai_driver_install(&g_config, &t_config, &f_config) != ESP_OK) {
    Serial.println("Failed to install driver");
    return;
  }

  if (twai_start() != ESP_OK) {
    Serial.println("Failed to start driver");
    return;
  }
}

void loop() {
  twai_message_t message;

  if (twai_receive(&message, pdMS_TO_TICKS(10000)) != ESP_OK) {
    return;
  }
  
  String payload = "";
  for (int i=0;i<message.data_length_code;i++) {
    if (i != 0) {
      payload += " ";
    }
    payload += "0x";
    if (message.data[i] < 0x10) {
      payload += "0";
    }
    payload += String(message.data[i], HEX);
  }
  Serial.printf("Received ID 0x%02x: %s\n", message.identifier, payload.c_str());
}