#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include "Adafruit_FRAM_I2C.h"
#include <Wire.h>

#include "OLEDs.h"

#define FRAM_ADDR 0x50  // the default address!
Adafruit_FRAM_I2C i2fram;

String Display1 = "OLED 1";  // Fiktiver Wert für Testzwecke
String saved;

#define LED_PIN 3;

void setup() {
  Serial.begin(9600);
  Wire.begin();
  uint16_t num;

  pinMode(LED_PIN, OUTPUT);

  if (i2fram.begin(FRAM_ADDR)) {  // you can stick the new i2c addr in here, e.g. begin(0x51);
    Serial.println("Found I2C EEPROM");
    TCA9548A(0);

    if (!display.begin(SSD1306_DISPLAYALLON_RESUME, SCREEN_I2C_ADDR)) {
      while (true)
        ;
    }
  } else {
    Serial.println("I2C EEPROM not identified ... check your connections?\r\n");
    while (1) delay(10);
  }

  i2fram.readObject(0x00, saved);  // Zuvor gespeicherter String wird aus FRAM gelesen
}

void loop() {
  oledDisplayCenter(0, saved);
}


sketch.ino

diagram.json

# Wokwi Library List
# See https://docs.wokwi.com/guides/libraries

Adafruit GFX Library
Adafruit SSD1306
TCA9548A
Adafruit FRAM I2C


libraries.txt

Animations.h

// Wokwi Custom Chip - For docs and examples see:
// https://docs.wokwi.com/chips-api/getting-started
//
// SPDX-License-Identifier: MIT
// Copyright 2023 

#include "wokwi-api.h"
#include <stdio.h>
#include <stdlib.h>

typedef struct {
  // TODO: Put your chip variables here
} chip_state_t;

void chip_init() {
  chip_state_t *chip = malloc(sizeof(chip_state_t));

  // TODO: Initialize the chip, set up IO pins, create timers, etc.

  printf("Hello from custom chip!\n");
}


tca9548a.chip.h

tca9548a

tca9548a.chip.json

// *********** Oleds.h ************* //

// Defines
#define SCREEN_I2C_ADDR 0x3C  // or 0x3C
#define SCREEN_WIDTH 128      // OLED display width, in pixels
#define SCREEN_HEIGHT 64      // OLED display height, in pixels
#define OLED_RST_PIN -1       // Reset pin (-1 if not available)

String inputString = "";         // a string to hold incoming data
boolean stringComplete = false;  // whether the string is complete
String commandString = "";

// Initial Display
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RST_PIN);

// Setup Multiplexer
void TCA9548A(uint8_t bus) {
  Wire.beginTransmission(0x70);  //TCA9548A address is 0x70
  Wire.write(1 << bus);          // send byte to select bus
  Wire.endTransmission();
}

// Format text and render
void oledDisplayCenter(int Display, String text) {
  int16_t x1;
  int16_t y1;
  uint16_t width;
  uint16_t height;

  display.getTextBounds(text, 0, 0, &x1, &y1, &width, &height);

  // display on horizontal and vertical center
  TCA9548A(Display);
  display.clearDisplay();  // clear display
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor((SCREEN_WIDTH - width) / 2, (SCREEN_HEIGHT - height) / 2);
  display.println(text);  // text to display
  display.display();
}

// Format text from SerialPort (App)
void getCommand() {
  if (inputString.length() > 0) {
    commandString = inputString.substring(1, 8);
  }
}

// Print text
String getTextToPrint() {
  String value = inputString.substring(8, inputString.length() - 2);
  return value;
}

// Listening to incoming data from SerialPort (App)
void serialEvent() {
  while (Serial.available()) {
    // get the new byte:
    char inChar = (char)Serial.read();
    // add it to the inputString:
    inputString += inChar;
    // if the incoming character is a newline, set a flag
    // so the main loop can do something about it:
    if (inChar == '\n') {
      stringComplete = true;
    }
  }
}