Smart Home Automation Forum - B8

SHT30 temp/humidity i2c sensor to Kincony B8

Fri, 20 Mar 2026 17:13:14 +0800

Hi,

I am trying to connect an SHT30 temperature and humidity i1c sensor to a Kincony B8 using free GPIOs 47 and 48. https://shop.kincony.com/products/sht30-...tion-cable

I have ESPHome firmware on the board with this config:

i2c:

- id: bus_b
sda: GPIO47
scl: GPIO48
scan: true
frequency: 100kHz

sensor:
- platform: sht3xd
i2c_id: bus_b
address: 0x44
update_interval: 60s
temperature:
name: "Homerseklet"
device_class: "temperature"
state_class: "measurement"
humidity:
name: "Paratartalom"
device_class: "humidity"
state_class: "measurement"

I have tried many variations, switching the SDA and SCL etc but no luck. The device is not detected. Am I using the correct GPIOs? (see attached photo)

black -> ground
yellow -> 47
blueish green -> 48
red -> 3V

20260319_164425.jpg (Size: 402.11 KB / Downloads: 65)

[arduino code examples for B8]-11 digital INPUT trigger OUTPUT directly

Mon, 23 Jun 2025 13:02:04 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * This program reads 8 input states from a PCF8575 I/O expander and 

 * controls a corresponding 8-channel relay module. When an input pin 

 * is LOW, the corresponding relay is turned ON (LOW means ON for the relay).

 * When the input pin is HIGH, the corresponding relay is turned OFF.

 */

#include         // I2C communication

#include      // Library to control the PCF8575 I/O expander

// Define I2C pins

#define SDA 8           // SDA pin

#define SCL 18           // SCL pin

// I2C addresses

#define RELAY_I2C_ADDRESS 0x22   // I2C address for the relay PCF8575 module

PCF8575 pcf8575_RL(RELAY_I2C_ADDRESS);    // Create an object for the relay PCF8575

void setup() {

  // Initialize I2C communication

  Wire.begin(SDA, SCL);

  // Initialize serial communication

  Serial.begin(115200);

  // Initialize input and relay modules

  pcf8575_RL.begin();

  // Turn off all relays at the start

  for (int i = 8; i < 16; i++) {

    pcf8575_RL.write(i, LOW);  // Assuming relays are LOW when OFF, setting all relays to OFF initially

  }

  Serial.println("System started: Input state controlling 8 relays");

}

void loop() {

  uint16_t inputState = 0;

  // Read the state of 16 inputs

  for (int i = 0; i < 8; i++) {

    if (pcf8575_RL.read(i)) {

      inputState |= (1 << i);  // If input is HIGH, set the corresponding bit

    } else {

      inputState &= ~(1 << i); // Otherwise, clear the corresponding bit

    }

  }

  // Control the relays based on the input state

  for (int i = 0; i < 8; i++) {

    if (inputState & (1 << i)) {

      pcf8575_RL.write(i+8, HIGH);  // If input is HIGH, turn the relay OFF

    } else {

      pcf8575_RL.write(i+8, LOW);   // If input is LOW, turn the relay ON

    }

  }

  // Delay for 500 milliseconds

  delay(500);

}

arduino ino file download:

11-input-trigger-output.zip (Size: 968 bytes / Downloads: 419)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

11-input-trigger-output.ino.merged.zip (Size: 192.21 KB / Downloads: 394)

[arduino code examples for B8]-10 Print TEXT on SSD1306 OLED displayer

Mon, 23 Jun 2025 13:00:01 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 * 

 * This Arduino program demonstrates how to display text on an SSD1306 128x64 OLED display using the U8g2 library.

 * The program draws two lines of text on the display:

 * - The first line is "KINCONY" in a larger font.

 * - The second line is "www.kincony.com" in a smaller font.

 * 

 * The display is connected via I2C (software implementation) with:

 * - SCL (clock) on pin IO18

 * - SDA (data) on pin IO8

 * 

 * The display's I2C address is set to 0x3C.

 */

#include   // Include the U8g2 library for controlling the OLED display

#include      // Include the Wire library for I2C communication

// Initialize the display using the software I2C method (SCL = IO18, SDA = IO8)

U8G2_SSD1306_128X64_NONAME_F_SW_I2C u8g2(U8G2_R0,  18, 8, U8X8_PIN_NONE);  // Screen rotation: U8G2_R0

// Function to display page 1 content

void page1() {

  // Set font size 18 for the larger "KINCONY" text

  u8g2.setFont(u8g2_font_timR18_tf);  // Use the Times Roman font, size 18

  u8g2.setFontPosTop();               // Set the text position at the top of the display

  u8g2.setCursor(5, 0);               // Position the cursor at coordinates (5, 0)

  u8g2.print("KINCONY");              // Display the text "KINCONY" on the screen

  // Set font size 12 for the smaller "www.kincony.com" text

  u8g2.setFont(u8g2_font_timR12_tf);  // Use the Times Roman font, size 12

  u8g2.setCursor(0, 40);              // Position the cursor at coordinates (0, 40)

  u8g2.print("www.kincony.com");      // Display the text "www.kincony.com"

}

// Setup function, runs once when the program starts

void setup() {

  // Set the I2C address for the display to 0x3C

  u8g2.setI2CAddress(0x3C*2);  // I2C address shift for 8-bit format

  // Initialize the display

  u8g2.begin();

  // Enable UTF-8 character printing for the display

  u8g2.enableUTF8Print();  // Allow UTF-8 encoded text to be printed

}

// Main loop function, continuously runs after setup()

void loop() {

  // Begin the display drawing process

  u8g2.firstPage();  // Prepare the first page for drawing

  do {

    // Call the page1() function to draw content on the display

    page1();

  } while (u8g2.nextPage());  // Continue to the next page until all pages are drawn

}

arduino ino file download:

10-oled-ssd1306.zip (Size: 1.11 KB / Downloads: 397)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

10-oled-ssd1306.ino.merged.zip (Size: 202.58 KB / Downloads: 356)

[arduino code examples for B8]-09 how to communication with Tuya WiFi module

Mon, 23 Jun 2025 12:58:36 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 * 

 * This Arduino program implements communication between ESP32 and the Tuya module

 * via UART (serial communication). It listens for specific packets from the Tuya module

 * and responds according to the predefined commands.

 * 

 * Functionality:

 * 1. When the ESP32 receives a heartbeat packet (55 AA 00 00 00 00 FF),

 *    it sends a heartbeat response (55 AA 03 00 00 01 00 03).

 * 2. When the ESP32 receives a product information request (55 AA 00 01 00 00 00),

 *    it sends a product information response (55 AA 03 01 ...).

 * 3. When the ESP32 receives a work mode request (55 AA 00 02 00 00 01),

 *    it sends a work mode response (55 AA 03 02 00 03 10 1C 14 47).

 * 4. When the ESP32 receives a network status request (55 AA 00 03 00 01 00 03),

 *    it sends a network status response (55 AA 03 03 00 00 05).

 * 5. Subsequent heartbeat packets (55 AA 00 00 00 00 FF) are responded to with

 *    (55 AA 03 00 00 01 01 04).

 */

#include 

// Create a HardwareSerial object for UART communication on ESP32

HardwareSerial tuyaSerial(1);

// Define the GPIO pins for TXD and RXD used for serial communication

#define TXD_PIN 16

#define RXD_PIN 17

// Set the baud rate for Tuya module communication to 9600

#define BAUD_RATE 9600

// Define the response packets for different commands from the Tuya module

// Heartbeat response: 55 AA 03 00 00 01 00 03

uint8_t heartBeatResponse[] = {0x55, 0xAA, 0x03, 0x00, 0x00, 0x01, 0x00, 0x03};

// Product info response with a detailed payload (e.g., firmware version, product name, etc.)

uint8_t productInfoResponse[] = {

  0x55, 0xAA, 0x03, 0x01, 0x00, 0x2A, 0x7B, 0x22, 0x70, 0x22, 0x3A, 0x22, 

  0x63, 0x68, 0x6D, 0x7A, 0x6C, 0x67, 0x6A, 0x70, 0x61, 0x64, 0x70, 0x71, 

  0x78, 0x64, 0x6B, 0x6F, 0x22, 0x2C, 0x22, 0x76, 0x22, 0x3A, 0x22, 0x31, 

  0x2E, 0x30, 0x2E, 0x30, 0x22, 0x2C, 0x22, 0x6D, 0x22, 0x3A, 0x30, 0x7D, 0xAA

};

// Work mode response: 55 AA 03 02 00 03 10 1C 14 47

uint8_t workModeResponse[] = {0x55, 0xAA, 0x03, 0x02, 0x00, 0x03, 0x10, 0x1C, 0x14, 0x47};

// Network status response: 55 AA 03 03 00 00 05

uint8_t netStatusResponse[] = {0x55, 0xAA, 0x03, 0x03, 0x00, 0x00, 0x05};

// Subsequent heartbeat response: 55 AA 03 00 00 01 01 04

uint8_t secondHeartBeatResponse[] = {0x55, 0xAA, 0x03, 0x00, 0x00, 0x01, 0x01, 0x04};

void setup() {

  // Initialize the serial communication for debugging at 115200 baud rate

  Serial.begin(115200);

  // Initialize the serial communication with Tuya module at 9600 baud rate

  tuyaSerial.begin(BAUD_RATE, SERIAL_8N1, RXD_PIN, TXD_PIN);

  // Debug message to indicate that the serial communication has been initialized

  Serial.println("ESP32-Tuya serial communication initialized.");

}

void loop() {

  // Check if data is available from the Tuya module

  if (tuyaSerial.available()) {

    uint8_t incomingPacket[7];  // Array to store the received packet

    size_t bytesRead = tuyaSerial.readBytes(incomingPacket, 7); // Read 7 bytes from Tuya

    // Check if the packet has a valid header (0x55, 0xAA)

    if (bytesRead >= 2 && incomingPacket[0] == 0x55 && incomingPacket[1] == 0xAA) {

      // If less than 7 bytes were received, wait for more data

      if (bytesRead < 7) {

        Serial.println("Incomplete packet received. Waiting for remaining bytes...");

        delay(50); // Delay to allow more data to be received

        while (tuyaSerial.available()) {

          incomingPacket[bytesRead++] = tuyaSerial.read(); // Continue reading remaining bytes

          if (bytesRead >= 7) break;

        }

      }

      // If still less than 7 bytes, discard the incomplete packet

      if (bytesRead < 7) {

        Serial.println("Error: Incomplete packet discarded.");

        return;

      }

      // Debug: Print the received packet for logging

      Serial.print("Received packet: ");

      for (size_t i = 0; i < 7; i++) {

        Serial.print(incomingPacket[i], HEX);

        Serial.print(" ");

      }

      Serial.println();

      // Call the function to process the received packet

      processTuyaPacket(incomingPacket, 7);

    } else {

      // If the header is invalid, discard the packet and flush the buffer

      Serial.print("Error: Invalid packet header. Data received: ");

      for (size_t i = 0; i < bytesRead; i++) {

        Serial.print(incomingPacket[i], HEX);

        Serial.print(" ");

      }

      Serial.println();

      tuyaSerial.flush(); // Clear the serial buffer

    }

  }

  // Delay to avoid CPU overuse

  delay(100);

}

// Function to process the received packet and send the appropriate response

void processTuyaPacket(uint8_t* packet, size_t size) {

  // Ensure the packet size is 7 and the header is valid

  if (size == 7 && packet[0] == 0x55 && packet[1] == 0xAA) {

    // Determine the command in the packet (packet[2])

    switch(packet[2]) {

      case 0x00:

        if (packet[3] == 0x00 && packet[4] == 0x00 && packet[5] == 0x00 && packet[6] == 0xFF) {

          Serial.println("Heartbeat received.");

          sendPacket(heartBeatResponse, sizeof(heartBeatResponse));

        } else if (packet[3] == 0x01 && packet[4] == 0x00 && packet[5] == 0x00 && packet[6] == 0x00) {

          Serial.println("Product info request received.");

          sendPacket(productInfoResponse, sizeof(productInfoResponse));

        } else if (packet[3] == 0x02 && packet[4] == 0x00 && packet[5] == 0x00 && packet[6] == 0x01) {

          Serial.println("Work mode request received.");

          sendPacket(workModeResponse, sizeof(workModeResponse));

        } else if (packet[3] == 0x03 && packet[4] == 0x00 && packet[5] == 0x01 && packet[6] == 0x00) {

          Serial.println("Network status request received.");

          sendPacket(netStatusResponse, sizeof(netStatusResponse));

        }

        break;

      default:

        Serial.println("Error: Unhandled command received.");

        break;

    }

  }

}

// Function to send the response packet to the Tuya module

void sendPacket(uint8_t* packet, size_t size) {

  // Send the packet via UART to Tuya module

  tuyaSerial.write(packet, size);

  // Debug: Print the sent packet for logging

  Serial.print("Sent packet: ");

  for (size_t i = 0; i < size; i++) {

    Serial.print(packet[i], HEX);

    Serial.print(" ");

  }

  Serial.println();

}

arduino ino file download:

9-tuya-wifi-config.zip (Size: 2 KB / Downloads: 382)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

9-tuya-wifi-config.ino.merged.zip (Size: 187.17 KB / Downloads: 397)

[arduino code examples for B8]-08 Ethernet W5500 chip work with TCP Server mode

Mon, 23 Jun 2025 12:56:18 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * This Arduino program sets up an ESP32-S3 with a W5500 Ethernet module

 * as a TCP server. It listens on port 4196 and echoes back any string 

 * received from a client.

 *

 * Hardware connections:

 * - CLK: GPIO42

 * - MOSI: GPIO43

 * - MISO: GPIO44

 * - CS: GPIO41

 * - RST: GPIO1

 * - INT: GPIO2

 *

 * Static IP address: 192.168.3.55

 * Subnet Mask: 255.255.255.0

 * Gateway: 192.168.3.1

 * DNS: 192.168.3.1

 */

#include 

#include 

// Define the W5500 Ethernet module pins

#define W5500_CS_PIN  42

#define W5500_RST_PIN 44

#define W5500_INT_PIN 43

#define W5500_CLK_PIN 1

#define W5500_MOSI_PIN 2

#define W5500_MISO_PIN 41

// MAC address for your Ethernet shield (must be unique on your network)

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };

// Static IP address configuration

IPAddress ip(192, 168, 3, 55);       // Static IP address

IPAddress subnet(255, 255, 255, 0);   // Subnet mask

IPAddress gateway(192, 168, 3, 1);    // Default gateway

IPAddress dns(192, 168, 3, 1);        // DNS server address

// Create an EthernetServer object to handle TCP connections

EthernetServer server(4196);

void setup() {

  // Initialize serial communication

  Serial.begin(115200);

  while (!Serial) {

    ; // Wait for serial port to connect

  }

  // Initialize the W5500 module

  pinMode(W5500_RST_PIN, OUTPUT);

  pinMode(W5500_INT_PIN, INPUT);

  digitalWrite(W5500_RST_PIN, LOW);  // Reset the W5500 module

  delay(100);                       // Wait for reset to complete

  digitalWrite(W5500_RST_PIN, HIGH); // Release reset

  // Initialize SPI with the correct pin definitions

  SPI.begin(W5500_CLK_PIN, W5500_MISO_PIN, W5500_MOSI_PIN);

  // Set up the Ethernet library with W5500-specific pins

  Ethernet.init(W5500_CS_PIN);

  // Start the Ethernet connection with static IP configuration

  Ethernet.begin(mac, ip, dns, gateway, subnet);

  // Print the IP address to the serial monitor

  Serial.print("IP Address: ");

  Serial.println(Ethernet.localIP());

  // Start listening for incoming TCP connections

  server.begin();

}

void loop() {

  // Check for incoming client connections

  EthernetClient client = server.available();

  if (client) {

    Serial.println("New client connected");

    // Read data from the client and echo it back

    while (client.connected()) {

      if (client.available()) {

        char c = client.read();

        server.write(c);

      }

    }

    // Close the connection when done

    client.stop();

    Serial.println("Client disconnected");

  }

}

arduino ino file download:

8-Ethernet-W5500.zip (Size: 1.23 KB / Downloads: 378)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

8-Ethernet-W5500.ino.merged.zip (Size: 191.06 KB / Downloads: 388)

[arduino code examples for B8]-07 how to DS3231 RTC clock

Mon, 23 Jun 2025 12:54:49 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * DS3231 RTC with Arduino

 *

 * This program demonstrates how to use the DS3231 RTC (Real-Time Clock) module with the Arduino.

 * It includes functionality to:

 * - Initialize the DS3231 RTC module

 * - Read the current date and time from the RTC

 * - Set the RTC time based on a serial command:Command format: DYYYY-MM-DDTHH:MM:SS

*    Set date and time command example: D2024-09-19T11:50:22

*    print current date and time command: current time

*

 *

 * Hardware Connections:

 * - SDA: GPIO 8

 * - SCL: GPIO 18

 */

#include 

#include 

String serial_cmd_rcv = ""; // Serial port receiver

typedef struct

{

  byte year;    // Last two digits of the year, library adds 2000.

  byte month;

  byte day;

  byte hour;

  byte minute;

  byte second;

} MY_DATE_STR;

MY_DATE_STR my_date_str = {0};

// Define constants for relay control

#define OPEN_RLY_DATA    26

#define OPEN_RLY_MONTH   4

#define CLOSE_RLY_DATA   2

#define CLOSE_RLY_MONTH  5

// Define pin connections

#define SDA_PIN   8

#define SCL_PIN   18

DS3231 rtc; // Create an instance of the DS3231 RTC

bool h12Flag;

bool pmFlag;

static bool bCentury = false;

static bool old_level_high = false;

static bool old_level_low = false;

/**

 * @brief Print the current time from the RTC to the Serial Monitor.

 */

static void PrintfCurTime()

{

  Serial.print("Current time is: ");

  int year = rtc.getYear() + 2000;

  Serial.print(year);

  Serial.print("-");

  Serial.print(rtc.getMonth(bCentury), DEC);

  Serial.print("-");

  Serial.print(rtc.getDate(), DEC);

  Serial.print(" ");

  Serial.print(rtc.getHour(h12Flag, pmFlag), DEC);

  Serial.print(":");

  Serial.print(rtc.getMinute(), DEC);

  Serial.print(":");

  Serial.println(rtc.getSecond(), DEC);

}

/**

 * @brief Process serial commands to set the RTC time.

 * Command format: DYYYY-MM-DDTHH:MM:SS

 */

static void GetSerialCmd()

{

  if (Serial.available() > 0)

  {

    delay(100);

    int num_read = Serial.available();

    while (num_read--)

      serial_cmd_rcv += char(Serial.read());

  }

  else return;

  serial_cmd_rcv.trim();

  if (serial_cmd_rcv == "current time")

  {

    PrintfCurTime();

    serial_cmd_rcv = "";

    return;

  }

  Serial.print("Received length: ");

  Serial.println(serial_cmd_rcv.length());

  int indexof_d = serial_cmd_rcv.indexOf('D');

  int indexof_t = serial_cmd_rcv.indexOf('T');

  Serial.print("D index: ");

  Serial.print(indexof_d);

  Serial.print(" T index: ");

  Serial.println(indexof_t);

  if (serial_cmd_rcv.length() != 20 || 

      serial_cmd_rcv.substring(0, 1) != "D" ||

      serial_cmd_rcv.substring(11, 12) != "T")  

  {

    Serial.println(serial_cmd_rcv);

    serial_cmd_rcv = "";

    return;

  }

  Serial.println("Setting time...");

  my_date_str.year = (byte)serial_cmd_rcv.substring(3, 5).toInt();

  my_date_str.month = (byte)serial_cmd_rcv.substring(6, 8).toInt();

  my_date_str.day = (byte)serial_cmd_rcv.substring(9, 11).toInt();

  my_date_str.hour = (byte)serial_cmd_rcv.substring(12, 14).toInt();

  my_date_str.minute = (byte)serial_cmd_rcv.substring(15, 17).toInt();

  my_date_str.second = (byte)serial_cmd_rcv.substring(18).toInt();

  rtc.setYear(my_date_str.year);

  rtc.setMonth(my_date_str.month);

  rtc.setDate(my_date_str.day);

  rtc.setHour(my_date_str.hour);

  rtc.setMinute(my_date_str.minute);

  rtc.setSecond(my_date_str.second);

  serial_cmd_rcv = "";

  Serial.println("Time set.");

}

void setup() {

  // Initialize the I2C interface

  Wire.begin(SDA_PIN, SCL_PIN, 40000);

  // Initialize Serial communication

  Serial.begin(115200);

  // Set the RTC to 24-hour mode

  rtc.setClockMode(false); // 24-hour format

  // Print current time to Serial Monitor

  PrintfCurTime();

  // Clear any remaining serial data

  while (Serial.read() >= 0) {}

}

void loop() {

  // Process incoming serial commands

  GetSerialCmd(); 

  delay(1000); // Delay for 1 second

}

arduino ino file download:

7-DS3231-RTC.zip (Size: 1.56 KB / Downloads: 346)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

7-DS3231-RTC.ino.merged.zip (Size: 193.65 KB / Downloads: 360)

[arduino code examples for B8]-06 How to use SD Card

Mon, 23 Jun 2025 12:53:26 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * SD Card File Operations

 *

 * This program demonstrates basic file operations on an SD card using the ESP32.

 * It includes functionality to:

 * - Initialize and test the SD card

 * - Read from, write to, append to, and delete files on the SD card

 * - Measure file read and write performance

 *

 * Hardware Connections:

 * - SCK: GPIO 11

 * - MISO: GPIO 12

 * - MOSI: GPIO 10

 * - CS: GPIO 9

 */

#include "FS.h"

#include "SD.h"

#include "SPI.h"

// Pin definitions for SD card

#define SCK  11

#define MISO 12

#define MOSI 10

#define CS   9

/**

 * @brief Reads the contents of a file from the SD card and prints it to the serial monitor.

 * 

 * @param fs File system to use (in this case, SD).

 * @param path Path of the file to read.

 */

void readFile(fs::FS &fs, const char * path) {

  Serial.printf("Reading file: %s\n", path);

  File file = fs.open(path);

  if (!file) {

    Serial.println("Failed to open file for reading");

    return;

  }

  Serial.print("Read from file: ");

  while (file.available()) {

    Serial.print((char)file.read());

  }

  file.close();

}

/**

 * @brief Writes a message to a file on the SD card.

 * 

 * @param fs File system to use (in this case, SD).

 * @param path Path of the file to write.

 * @param message Message to write to the file.

 */

void writeFile(fs::FS &fs, const char * path, const char * message) {

  Serial.printf("Writing file: %s\n", path);

  File file = fs.open(path, FILE_WRITE);

  if (!file) {

    Serial.println("Failed to open file for writing");

    return;

  }

  if (file.print(message)) {

    Serial.println("File written");

  } else {

    Serial.println("Write failed");

  }

  file.close();

}

/**

 * @brief Appends a message to a file on the SD card.

 * 

 * @param fs File system to use (in this case, SD).

 * @param path Path of the file to append.

 * @param message Message to append to the file.

 */

void appendFile(fs::FS &fs, const char * path, const char * message) {

  Serial.printf("Appending to file: %s\n", path);

  File file = fs.open(path, FILE_APPEND);

  if (!file) {

    Serial.println("Failed to open file for appending");

    return;

  }

  if (file.print(message)) {

    Serial.println("Message appended");

  } else {

    Serial.println("Append failed");

  }

  file.close();

}

/**

 * @brief Deletes a file from the SD card.

 * 

 * @param fs File system to use (in this case, SD).

 * @param path Path of the file to delete.

 */

void deleteFile(fs::FS &fs, const char * path) {

  Serial.printf("Deleting file: %s\n", path);

  if (fs.remove(path)) {

    Serial.println("File deleted");

  } else {

    Serial.println("Delete failed");

  }

}

/**

 * @brief Tests file read and write performance.

 * 

 * @param fs File system to use (in this case, SD).

 * @param path Path of the file to test.

 */

void testFileIO(fs::FS &fs, const char * path) {

  File file = fs.open(path);

  static uint8_t buf[512];

  size_t len = 0;

  uint32_t start = millis();

  uint32_t end = start;

  if (file) {

    len = file.size();

    size_t flen = len;

    start = millis();

    while (len) {

      size_t toRead = len;

      if (toRead > 512) {

        toRead = 512;

      }

      file.read(buf, toRead);

      len -= toRead;

    }

    end = millis() - start;

    Serial.printf("%u bytes read for %u ms\n", flen, end);

    file.close();

  } else {

    Serial.println("Failed to open file for reading");

  }

  file = fs.open(path, FILE_WRITE);

  if (!file) {

    Serial.println("Failed to open file for writing");

    return;

  }

  size_t i;

  start = millis();

  for (i = 0; i < 2048; i++) {

    file.write(buf, 512);

  }

  end = millis() - start;

  Serial.printf("%u bytes written for %u ms\n", 2048 * 512, end);

  file.close();

}

void setup() {

  // Initialize serial communication

  Serial.begin(115200);

  // Initialize SPI and SD card

  SPIClass spi = SPIClass(HSPI);

  spi.begin(SCK, MISO, MOSI, CS);

  if (!SD.begin(CS, spi, 80000000)) {

    Serial.println("Card Mount Failed");

    return;

  }

  uint8_t cardType = SD.cardType();

  if (cardType == CARD_NONE) {

    Serial.println("No SD card attached");

    return;

  }

  Serial.print("SD Card Type: ");

  if (cardType == CARD_MMC) {

    Serial.println("MMC");

  } else if (cardType == CARD_SD) {

    Serial.println("SDSC");

  } else if (cardType == CARD_SDHC) {

    Serial.println("SDHC");

  } else {

    Serial.println("UNKNOWN");

  }

  uint64_t cardSize = SD.cardSize() / (1024 * 1024);

  Serial.printf("SD Card Size: %lluMB\n", cardSize);

  delay(2000);

  // Perform file operations

  deleteFile(SD, "/hello.txt");

  writeFile(SD, "/hello.txt", "Hello ");

  appendFile(SD, "/hello.txt", "World!\n");

  readFile(SD, "/hello.txt");

  testFileIO(SD, "/test.txt");

  Serial.printf("Total space: %lluMB\n", SD.totalBytes() / (1024 * 1024));

  Serial.printf("Used space: %lluMB\n", SD.usedBytes() / (1024 * 1024));

}

void loop() {

  // No operation in loop

}

arduino ino file download:

6-SD.zip (Size: 1.53 KB / Downloads: 358)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

6-SD.ino.merged.zip (Size: 219.15 KB / Downloads: 368)

[arduino code examples for B8]-05 Read free GPIO state

Mon, 23 Jun 2025 12:48:27 +0800

Code:
/*

 * ESP32 GPIO State Reader

 * Reads the state of GPIO47, GPIO48, GPIO7, GPIO40, GPIO0, and GPIO5

 * and prints the results to the serial monitor.

 * 

 * Made by KinCony IoT: https://www.kincony.com

 */

#define GPIO_13  13

#define GPIO_40  40

#define GPIO_14  14

#define GPIO_48  48

#define GPIO_0   0

#define GPIO_47  47

#define GPIO_7  7

#define GPIO_21  21

void setup() {

    Serial.begin(115200); // Initialize serial communication at 115200 baud rate

    // Set GPIOs as input

    pinMode(GPIO_13, INPUT);

    pinMode(GPIO_40, INPUT);

    pinMode(GPIO_14, INPUT);

    pinMode(GPIO_48, INPUT);

    pinMode(GPIO_0, INPUT);

    pinMode(GPIO_47, INPUT);

    pinMode(GPIO_7, INPUT);

    pinMode(GPIO_21, INPUT);            

}

void loop() {

    // Read GPIO states

    int state_13 = digitalRead(GPIO_13);

    int state_40 = digitalRead(GPIO_40);

    int state_14  = digitalRead(GPIO_14);

    int state_48 = digitalRead(GPIO_48);

    int state_0  = digitalRead(GPIO_0);

    int state_47 = digitalRead(GPIO_47);

    int state_7 = digitalRead(GPIO_7);

    int state_21 = digitalRead(GPIO_21);

    // Print GPIO states to the serial monitor

    Serial.printf("GPIO13: %d, GPIO40: %d, GPIO14: %d, GPIO48: %d, GPIO0: %d, GPIO47: %d, GPIO7: %d, GPIO21: %d\n",

                  state_13, state_40, state_14, state_48, state_0, state_47, state_7, state_21);

    delay(1000); // Read GPIO states every second

}

arduino ino file download:

5-free-gpio-state.zip (Size: 682 bytes / Downloads: 380)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

5-free-gpio-state.ino.merged.zip (Size: 181.54 KB / Downloads: 372)

[arduino code examples for B8]-04 RS485 communication test

Mon, 23 Jun 2025 12:43:46 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * RS485 Communication Test

 *

 * This program is a simple test for RS485 communication using ESP32-S3.

 * It will send a message over RS485 and then read incoming messages.

 * The TXD pin is defined as GPIO 18 and RXD pin is defined as GPIO 8.

 */

#include 

// Define RS485 pins

#define RS485_RXD 38

#define RS485_TXD 39

// Create a hardware serial object

HardwareSerial rs485Serial(1);

void setup() {

  // Start serial communication for debugging

  Serial.begin(115200);

  while (!Serial);

  // Initialize RS485 Serial communication

  rs485Serial.begin(9600, SERIAL_8N1, RS485_RXD, RS485_TXD);

  Serial.println("RS485 Test Start");

}

void loop() {

  // Send a test message

  rs485Serial.println("Hello from KinCony B8M!");

  // Wait for a short period

  delay(1000);

  // Check if data is available to read

  if (rs485Serial.available()) {

    String receivedMessage = "";

    while (rs485Serial.available()) {

      char c = rs485Serial.read();

      receivedMessage += c;

    }

    // Print the received message

    Serial.print("Received: ");

    Serial.println(receivedMessage);

  }

  // Wait before sending the next message

  delay(2000);

}

arduino ino file download:

4-RS485-Test.zip (Size: 763 bytes / Downloads: 351)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

4-RS485-Test.ino.merged.zip (Size: 186.52 KB / Downloads: 366)

[arduino code examples for B8]-03 Read ADS1115 analog input ports value

Mon, 23 Jun 2025 12:40:28 +0800

Code:
/*

 * This program reads voltage values from the ADS1115 analog-to-digital converter

 * on all four channels (A0, A1, A2, A3) and prints the results through the serial port.

 * The ADS1115 communicates via the I2C protocol. This version of the code includes 

 * the capability to specify custom SDA and SCL pins for I2C communication.

 *

 * Copyright: Made by KinCony IoT: https://www.kincony.com

 *

 */

#include                 // Library for I2C communication

#include      // Library for ADS1115 ADC module

// Define the I2C SDA and SCL pins for communication with ADS1115

#define SDA_PIN 8  

#define SCL_PIN 18  

// Initialize ADS1115 instance using the Wire library

DFRobot_ADS1115 ads(&Wire);

void setup(void) 

{

    // Begin serial communication at a baud rate of 115200

    Serial.begin(115200);

    // Initialize the I2C bus using the defined SDA and SCL pins

    Wire.begin(SDA_PIN, SCL_PIN);

    // Set the I2C address for the ADS1115 (default: 0x49)

    ads.setAddr_ADS1115(ADS1115_IIC_ADDRESS0);   // Address is 0x49

    // Set the gain for the ADS1115 (2/3x gain allows for a maximum input voltage of 6.144V)

    ads.setGain(eGAIN_TWOTHIRDS);

    // Set the ADS1115 to operate in single-shot mode (each reading is a single conversion)

    ads.setMode(eMODE_SINGLE);

    // Set the sample rate to 128 samples per second (SPS)

    ads.setRate(eRATE_128);

    // Set the operational status mode to single-conversion start

    ads.setOSMode(eOSMODE_SINGLE);

    // Initialize the ADS1115 module

    ads.init();

}

void loop(void) 

{

    // Check if the ADS1115 is properly connected and functioning

    if (ads.checkADS1115())

    {

        // Variables to store the voltage readings for each channel

        int16_t adc0, adc1, adc2, adc3;

        // Read the voltage from channel A0 and print the value

        adc0 = ads.readVoltage(0);

        Serial.print("A0:");

        Serial.print(adc0);

        Serial.print("mV,  ");    // Print the value in millivolts

        // Read the voltage from channel A1 and print the value

        adc1 = ads.readVoltage(1);

        Serial.print("A1:");

        Serial.print(adc1);

        Serial.print("mV,  ");    // Print the value in millivolts

        // Read the voltage from channel A2 and print the value

        adc2 = ads.readVoltage(2);

        Serial.print("A2:");

        Serial.print(adc2);

        Serial.print("mV,  ");    // Print the value in millivolts

        // Read the voltage from channel A3 and print the value

        adc3 = ads.readVoltage(3);

        Serial.print("A3:");

        Serial.print(adc3);

        Serial.println("mV");     // Print the value in millivolts and end the line

    }

    else

    {

        // If ADS1115 is not connected, print a message indicating disconnection

        Serial.println("ADS1115 Disconnected!");

    }

    // Wait for 1 second before the next loop iteration

    delay(1000);

}

arduino ino file download:

3-ads1115_adc.zip (Size: 1.2 KB / Downloads: 345)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

3-ads1115_adc.ino.merged.zip (Size: 192.69 KB / Downloads: 367)

[arduino code examples for B8]-02 Read digital input ports state

Mon, 23 Jun 2025 12:36:15 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * Description:

 * This Arduino program reads the state of a 16-channel PCF8575 I/O expander

 * and prints the state of all input pins to the Serial Monitor. The state of 

 * each pin is represented as a bit in a 16-bit value, where each bit corresponds 

 * to an input pin. The program prints the input state in binary format.

 *

 * Pin Definitions:

 * - SDA: GPIO 8

 * - SCL: GPIO 18

 * - PCF8575 I2C Address: 0x22

 */

#include "Arduino.h"

#include "PCF8575.h"

// Define I2C pins

#define I2C_SDA 8  // Define SDA pin

#define I2C_SCL 18  // Define SCL pin

// Set I2C address

PCF8575 pcf8575_IN1(0x22); // The I2C address of the PCF8575

void setup() {

    Serial.begin(115200);

    // Initialize I2C communication

    Wire.begin(I2C_SDA, I2C_SCL); // Initialize I2C with defined SDA and SCL pins

    pcf8575_IN1.begin(); // Initialize the PCF8575

    Serial.println("KinCony B8M 8 channel input state 0:ON  1:OFF");

}

void loop() {

    uint16_t state = 0;

    // Read the state of each pin (assuming 16 pins)

    for (int pin = 0; pin < 8; pin++) {

        if (pcf8575_IN1.read(pin)) {

            state |= (1 << pin); // Set the bit for the active pin

        }

    }

    Serial.print("Input state: ");

    Serial.println(state, BIN); // Print the state of inputs in binary

    delay(500); // Delay 500ms

}

arduino ino file download:

2-digital-input.zip (Size: 837 bytes / Downloads: 348)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

2-digital-input.ino.merged.zip (Size: 192.29 KB / Downloads: 389)

[arduino code examples for B8]-01 Turn ON/OFF OUTPUT

Mon, 23 Jun 2025 12:31:00 +0800

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * This program controls a 16-channel relay board via a PCF8575 I/O expander.

 * It sequentially turns on each relay and then turns them off in a loop.

 * 

 * Pin Definitions:

 * - SDA: GPIO 8

 * - SCL: GPIO 18

 * 

 * Delay Time:

 * - 200 milliseconds between switching relays

 */

#include         // Include the Wire library for I2C communication

#include      // Include the PCF8575 library to control the I/O expander

#define SDA 8           // Define the SDA pin

#define SCL 18          // Define the SCL pin

#define DELAY_TIME 200   // Define the delay time in milliseconds

// Set I2C address of the PCF8575 module

#define I2C_ADDRESS 0x22 // I2C address of the PCF8575 module

PCF8575 pcf8575_R1(I2C_ADDRESS); // Create a PCF8575 object with the specified I2C address

void setup() {

  // Initialize I2C communication

  Wire.begin(SDA, SCL); // SDA on GPIO 8, SCL on GPIO 18 (according to your board's configuration)

  // Initialize serial communication for debugging (optional)

  Serial.begin(115200);

  Serial.println("PCF8575 Relay Control: Starting...");

  // Initialize the PCF8575 module

  pcf8575_R1.begin();

  // Turn off all relays initially (set all pins HIGH)

  for (int i = 8; i < 16; i++) {

    pcf8575_R1.write(i, HIGH); // Set all relays to OFF (assuming HIGH means OFF for relays)

  }

}

void loop() {

  // Sequentially turn on each relay

  for (int i = 8; i < 16; i++) {

    pcf8575_R1.write(i, LOW);   // Turn on the relay at pin i (LOW means ON for the relay)

    delay(DELAY_TIME);          // Wait for DELAY_TIME milliseconds

  }

  // Sequentially turn off each relay

  for (int i = 8; i < 16; i++) {

    pcf8575_R1.write(i, HIGH);  // Turn off the relay at pin i (HIGH means OFF for the relay)

    delay(DELAY_TIME);          // Wait for DELAY_TIME milliseconds

  }

}

arduino ino file download:

1-output.zip (Size: 927 bytes / Downloads: 361)
BIN file (you can use esp32 download tool download to ESP32-S3 with address 0x0 then directly to use) download:

1-output.ino.merged.zip (Size: 192.06 KB / Downloads: 357)

B8 ESPHome yaml for home assistant with tuya

Mon, 23 Jun 2025 12:28:31 +0800

Code:
esphome:

  name: b8

  friendly_name: b8

  platformio_options:

    board_build.extra_flags:

      # WIFI_CONTROL_SELF_MODE = 0

      # WIFI_CONTROL_SELF_MODE = 1

      - "-DWIFI_CONTROL_SELF_MODE=1"

esp32:

  board: esp32-s3-devkitc-1

  framework:

    type: arduino

external_components:

  - source:

      type: git

      url: https://github.com/hzkincony/esphome-tuya-wifi-mcu

      ref: v1.1.0

# Enable logging

# logger: 

#   hardware_uart: USB_SERIAL_JTAG

# Enable Home Assistant API

api:

  encryption:

    key: "WeVOuL5oNhjXcfzXtTirlOwvtWvCD5yqIxd3oV4es1k="

ethernet:

  type: W5500

  clk_pin: GPIO1

  mosi_pin: GPIO2

  miso_pin: GPIO41

  cs_pin: GPIO42

  interrupt_pin: GPIO43

  reset_pin: GPIO44

i2c:

   - id: bus_a

     sda: 8

     scl: 18

     scan: true

     frequency: 400kHz

pcf8574:

  - id: 'pcf8574_hub_out_1'  # for output channel 0-7| input channel 8-15   

    i2c_id: bus_a

    address: 0x22

    pcf8575: true

uart:

  - id: uart_1    #RS485

    baud_rate: 9600

    debug:

      direction: BOTH

      dummy_receiver: true

      after:

        timeout: 10ms

    tx_pin: 39

    rx_pin: 38

  - id: tuya_mcu_uart

    tx_pin: GPIO16

    rx_pin: GPIO17

    baud_rate: 9600

tuya_wifi_mcu:

  # tuya mcu product id

  product_id: tugmdoiviinh13kv

  uart_id: tuya_mcu_uart

  wifi_reset_pin: 28

  wifi_led_pin: 16

switch:

  - platform: uart

    uart_id: uart_1

    name: "RS485 Button"

    data: [0x11, 0x22, 0x33, 0x44, 0x55]

  - platform: gpio

    name: "b8-output01"

    id: "b8_output01"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 8

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output1-tuya

    dp_id: 1

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output01"

  - platform: gpio

    name: "b8-output02"

    id: "b8_output02"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 9

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output2-tuya

    dp_id: 2

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output02"

  - platform: gpio

    name: "b8-output03"

    id: "b8_output03"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 10

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output3-tuya

    dp_id: 3

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output03"

  - platform: gpio

    name: "b8-output04"

    id: "b8_output04"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 11

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output4-tuya

    dp_id: 4

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output04"

  - platform: gpio

    name: "b8-output05"

    id: "b8_output05"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 12

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output5-tuya

    dp_id: 5

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output05"

  - platform: gpio

    name: "b8-output06"

    id: "b8_output06"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 13

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output6-tuya

    dp_id: 6

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output06"

  - platform: gpio

    name: "b8-output07"

    id: "b8_output07"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 14

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output7-tuya

    dp_id: 101

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output07"

  - platform: gpio

    name: "b8-output08"

    id: "b8_output08"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 15

      mode: OUTPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-output8-tuya

    dp_id: 102

    # hide from homeassistant ui

    internal: true

    # bind other switch, sync state

    bind_switch_id: "b8_output08"

binary_sensor:

  - platform: gpio

    name: "b8-input01"

    id: "b8_input01"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 0

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input1-tuya

    dp_id: 111

    bind_binary_sensor_id: b8_input01

    internal: true

  - platform: gpio

    name: "b8-input02"

    id: "b8_input02"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 1

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input2-tuya

    dp_id: 112

    bind_binary_sensor_id: b8_input02

    internal: true

  - platform: gpio

    name: "b8-input03"

    id: "b8_input03"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 2

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input3-tuya

    dp_id: 113

    bind_binary_sensor_id: b8_input03

    internal: true

  - platform: gpio

    name: "b8-input04"

    id: "b8_input04"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 3

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input4-tuya

    dp_id: 114

    bind_binary_sensor_id: b8_input04

    internal: true

  - platform: gpio

    name: "b8-input05"

    id: "b8_input05"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 4

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input5-tuya

    dp_id: 115

    bind_binary_sensor_id: b8_input05

    internal: true

  - platform: gpio

    name: "b8-input06"

    id: "b8_input06"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 5

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input6-tuya

    dp_id: 116

    bind_binary_sensor_id: b8_input06

    internal: true

  - platform: gpio

    name: "b8-input07"

    id: "b8_input07"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 6

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input7-tuya

    dp_id: 117

    bind_binary_sensor_id: b8_input07

    internal: true

  - platform: gpio

    name: "b8-input08"

    id: "b8_input08"

    pin:

      pcf8574: pcf8574_hub_out_1

      number: 7

      mode: INPUT

      inverted: true

  - platform: tuya_wifi_mcu

    name: b8-input8-tuya

    dp_id: 118

    bind_binary_sensor_id: b8_input08

    internal: true

##pull-up resistance on PCB

  - platform: gpio

    name: "b8-W1-io47"

    pin: 

      number: 47

      inverted: true

  - platform: gpio

    name: "b8-W1-io48"

    pin: 

      number: 48

      inverted: true

  - platform: gpio

    name: "b8-W1-io7"

    pin: 

      number: 7

      inverted: true

  - platform: gpio

    name: "b8-W1-io40"

    pin: 

      number: 40

      inverted: true

## without resistance on PCB

  - platform: gpio

    name: "b8-13"

    pin: 

      number: 13

      inverted:  false

  - platform: gpio

    name: "b8-14"

    pin: 

      number: 14

      inverted:  false

  - platform: gpio

    name: "b8-21"

    pin: 

      number: 21

      inverted:  false

  - platform: gpio

    name: "b8-0"

    pin: 

      number: 0

      inverted:  false

ads1115:

  - address: 0x48

sensor:

  - platform: ads1115

    multiplexer: 'A0_GND'

    gain: 6.144

    resolution: 16_BITS

    name: "ADS1115 Channel A0-GND"

    update_interval: 5s

  - platform: ads1115

    multiplexer: 'A1_GND'

    gain: 6.144

    name: "ADS1115 Channel A1-GND"

    update_interval: 5s

  - platform: ads1115

    multiplexer: 'A2_GND'

    gain: 6.144

    name: "ADS1115 Channel A2-GND"

    update_interval: 5s

  - platform: ads1115

    multiplexer: 'A3_GND'

    gain: 6.144

    name: "ADS1115 Channel A3-GND"

    update_interval: 5s

web_server:

  port: 80

font:

  - file: "gfonts://Roboto"

    id: roboto

    size: 20

display:

  - platform: ssd1306_i2c

    i2c_id: bus_a

    model: "SSD1306 128x64"

    address: 0x3C

    lambda: |-

      it.printf(0, 0, id(roboto), "KinCony b8");

download yaml file:

B8-HA.txt (Size: 8.35 KB / Downloads: 267)

B8 ESP32-S3 IO pins define

Mon, 23 Jun 2025 12:19:11 +0800

IIC Bus:

SDA:GPIO8
SCL:GPIO18

PCF8575: i2c address:0x22

PCF8575->P0 (digital input-1)
PCF8575->P1 (digital input-2)
PCF8575->P2 (digital input-3)
PCF8575->P3 (digital input-4)
PCF8575->P4 (digital input-5)
PCF8575->P5 (digital input-6)
PCF8575->P6 (digital input-7)
PCF8575->P7 (digital input-8)

PCF8575->P8 (relay1)
PCF8575->P9 (relay2)
PCF8575->P10 (relay3)
PCF8575->P11 (relay4)
PCF8575->P12 (relay5)
PCF8575->P13 (relay6)
PCF8575->P14 (relay7)
PCF8575->P15 (relay8)

24C02 EPROM i2c address: 0x50
DS3231 RTC i2c address: 0x68
SSD1306 display: i2c address:0x3c
ADS1115 (4CH ADC): i2c address:0x48

Analog input (A1: DC 0-5v)
Analog input (A2: DC 0-5v)
Analog input (A3: DC 4-20mA)
Analog input (A4: DC 4-20mA)

-----------------
1-wire GPIOs (with pull-up resistance on PCB):
1-wire-1:GPIO47
1-wire-2:GPIO48
1-wire-3:GPIO7
1-wire-4:GPIO40
-----------------
free GPIOs (without pull-up resistance on PCB):
GPIO13
GPIO14
GPIO21
-----------------

Ethernet (W5500) I/O define:

clk_pin: GPIO1
mosi_pin: GPIO2
miso_pin: GPIO41
cs_pin: GPIO42

interrupt_pin: GPIO43
reset_pin: GPIO44

--------------------
RS485:
RXD:GPIO38
TXD:GPIO39

Tuya module:
RXD:GPIO17
TXD:GPIO16

Tuya network button: Tuya module's P28
Tuya network LED: Tuya module's P16
--------------------
SD Card:
SPI-MOSI:GPIO10
SPI-SCK:GPIO11
SPI-MISO:GPIO12
SPI-CS:GPIO9
SPI-CD:GPIO5