#include <Arduino.h>
#include <U8g2lib.h>

// IMPORTANT: Changed the last parameter from 15 to U8X8_PIN_NONE.
// This prevents the library from resetting the first display when initializing the second.
U8G2_SSD1320_160X132_F_4W_SW_SPI lcd1(U8G2_R0, /* clock=*/18, /* data=*/23, /* cs=*/4, /* dc=*/2, /* reset=*/U8X8_PIN_NONE);
U8G2_SSD1320_160X132_F_4W_SW_SPI lcd2(U8G2_R2, /* clock=*/18, /* data=*/23, /* cs=*/5, /* dc=*/2, /* reset=*/U8X8_PIN_NONE);

int x_pos = 160; // Start position (off-screen right)

void setup(void)
{
  // 1. Manually reset BOTH displays ONCE at startup
  pinMode(15, OUTPUT);
  digitalWrite(15, LOW);
  delay(10);
  digitalWrite(15, HIGH);
  delay(10);

  // 2. Initialize BOTH displays.
  // Because we used U8X8_PIN_NONE, this will NOT toggle the reset pin again.
  lcd1.begin();
  lcd2.begin();

  // Set a large, readable font for both
  lcd1.setFont(u8g2_font_10x20_tr);
  lcd2.setFont(u8g2_font_10x20_tr);
}

void loop(void)
{
  // ==========================================
  // 1. Draw and send to LCD 1 (Left Half / CS Pin 4)
  // ==========================================
  lcd1.clearBuffer();
  lcd1.drawStr(x_pos, 60, "Hello World!");
  lcd1.sendBuffer(); // Activates CS pin 4 and updates the screen

  // Small delay to visually prove the CS pins are separated and working independently
  // delay(30);

  // ==========================================
  // 2. Draw and send to LCD 2 (Right Half / CS Pin 5)
  // ==========================================
  lcd2.clearBuffer();

  // Seamless 320px scrolling: subtract 160 so it flows smoothly from the right screen into the left screen
  lcd2.drawStr(x_pos - 160, 60, "Hello World!");

  lcd2.sendBuffer(); // Activates CS pin 5 and updates the screen

  // Move the text to the left for the next frame
  x_pos -= 2;

  // Reset position when it goes completely off the left side
  if (x_pos < -120)
  {
    x_pos = 160;
  }

  delay(2); // Control animation speed
}