/*
  Wokwi | questions
  MCP23017 assistance

  Wokwi | general
  AvenParker — 12:06 PM Saturday, November 29, 2025
  Hello Everyone, How can i add MCP23017 I/O module and I2C mux TCA9548A
  to the work space and work this with ESP32 and micropython? can someone
  please help?

*/

#include <Wire.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_GFX.h>
//#include "MCP23017.h"  // cool custom library
#include <Adafruit_MCP23X17.h>

#define OLED_ADDR 0x3C
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
//MCP23017 mcp;
Adafruit_MCP23X17 mcp;

int MCP_PINS[16];

const uint8_t MCP_PIN = 0; // GPA0
const uint8_t MON_PIN = 2; // monitor pin

void setup() {
  Serial.begin(9600);
  Wire.begin();



  // Initialize OLED
  display.setRotation(2);
  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println(F("OLED init failed"));
    while (1);
  }


  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("Hello :)"); //hi future me
  display.display();

  for (int pin = 0; pin < 16; pin++)  {
    MCP_PINS[pin] = pin;
  }

  // Setup MCP23017 at address 0x20
  //mcp.begin(0); // address 0 (defined by grounding all A pins)
  if (!mcp.begin_I2C(0x20)) {
    Serial.println(F("MCP init failed"));
    while (1);
  }
  //mcp.pinMode(MCP_PIN, OUTPUT); //output
  for (int pin = 0; pin < 16; pin++)  {
    mcp.pinMode(MCP_PINS[pin], OUTPUT);
  }

  // Setup Arduino D2 to read from MCP output
  //pinMode(MON_PIN, INPUT);

  Serial.println("Setup done.");
}

void loop() {

  for (int count = 0; count < 16; count++)  {
    mcp.digitalWrite(MCP_PINS[count], LOW);
    delay(500);
    mcp.digitalWrite(MCP_PINS[count], HIGH);
  }
  /*
    // Toggle MCP pin HIGH
    mcp.digitalWrite(MCP_PIN, HIGH);
    //mcp.writeGPIOB(MCP_PIN, HIGH);
    //delay(1000);
    Serial.print("MCP23017 GPA0: HIGH | Arduino D2 reads: ");
    Serial.println(digitalRead(MON_PIN));
    delay(1000);

    // Toggle MCP pin LOW
    mcp.digitalWrite(MCP_PIN, LOW);
    //mcp.writeGPIOB(MCP_PIN, LOW);
    //delay(1000);
    Serial.print("MCP23017 GPA0: LOW  | Arduino D2 reads: ");
    Serial.println(digitalRead(MON_PIN));
    delay(1000);

    Serial.println("I------------------------I");
  */
}