'display' was not declared in this scope problem while using Arduino Nano 33 BLE sense

Using Arduino Microcontrollers
1 
#include <ArduinoBLE.h>
// #include <ArduinoLowPower.h>
#include <GxEPD2_BW.h>
#include <GxEPD2_3C.h>
#include <GxEPD2_7C.h>
#include <Fonts/FreeMonoBold9pt7b.h>
#include "GxEPD2_display_selection_new_style.h"
#include "GxEPD2_display_selection.h"
#include "GxEPD2_display_selection_added.h"

// // Bluetooth® Low Energy Battery Service
//BLEService sbService("180F");
//
//// Bluetooth® Low Energy Battery Level Characteristic
//BLEUnsignedCharCharacteristic batteryLevelChar("2A19",  // standard 16-bit characteristic UUID
//    BLERead | BLENotify); // remote clients will be able to get notifications if this characteristic changes


BLEService smartBinService("19B10010-E8F2-537E-4F6C-D1047652ABCD"); // create service

// create switch characteristic and allow remote device to read and write
BLEUnsignedCharCharacteristic weightCharacteristic("19B10010-E8F2-537E-4F6C-D1047652ABC1", BLERead | BLENotify);
// create button characteristic and allow remote device to get notifications
BLEUnsignedCharCharacteristic levelCharacteristic("19B10010-E8F2-537E-4F6C-D1047652ABC2", BLERead | BLENotify);
BLEStringCharacteristic itemNameCharacteristic( "19B10010-E8F2-537E-4F6C-D1047652ABC3", BLERead | BLEWrite, 20 );
BLEStringCharacteristic itemBinPositionCharacteristic( "19B10010-E8F2-537E-4F6C-D1047652ABC4", BLERead | BLEWrite, 5 );
BLEUnsignedCharCharacteristic itemMaxWeightCharacteristic( "19B10010-E8F2-537E-4F6C-D1047652ABC5", BLERead | BLEWrite);



int sensorPin = A1;   // select the input pin for the potentiometer
int oldWeight = 0;  // last battery level reading from analog input
int oldLevel = 0;  // last battery level reading from analog input
int eink_weight_level = 0;
long previousMillis = 0;  // last time the battery level was checked, in ms
int green = 2;
int red = 3;
int refresh_rate = 30000;



void setup() {
  Serial.begin(9600);    // initialize serial communication
  //while (!Serial);

  pinMode(red, OUTPUT); //define red pin
  pinMode(green, OUTPUT); //define green pin
  pinMode(LED_BUILTIN, OUTPUT); // initialize the built-in LED pin to indicate when a central is connected

  // begin initialization
  if (!BLE.begin()) {
    Serial.println("starting BLE failed!");

    while (1);
  }

  einkDisplay_setup();

  /* Set a local name for the Bluetooth® Low Energy device
     This name will appear in advertising packets
     and can be used by remote devices to identify this Bluetooth® Low Energy device
     The name can be changed but maybe be truncated based on space left in advertisement packet
  */
  BLE.setLocalName("WeightMonitor");
  BLE.setDeviceName("WeightMonitor");

  
  BLE.setAdvertisedService(smartBinService); // add the service UUID
  smartBinService.addCharacteristic(weightCharacteristic); // add the weight characteristic
  smartBinService.addCharacteristic(levelCharacteristic); // add the weight level characteristic
  smartBinService.addCharacteristic(itemNameCharacteristic); // add the item name characteristic
  smartBinService.addCharacteristic(itemBinPositionCharacteristic); // add the bin position characteristic
  smartBinService.addCharacteristic(itemMaxWeightCharacteristic); // add the item max weight characteristic
  
  BLE.addService(smartBinService); // Add the battery service
  weightCharacteristic.writeValue(oldWeight); // set initial value for this characteristic
  levelCharacteristic.writeValue(oldLevel); // set initial value for this characteristic
  itemNameCharacteristic.writeValue("Not Set");
  itemBinPositionCharacteristic.writeValue("NA");
  itemMaxWeightCharacteristic.writeValue(50);



  /* Start advertising Bluetooth® Low Energy.  It will start continuously transmitting Bluetooth® Low Energy
     advertising packets and will be visible to remote Bluetooth® Low Energy central devices
     until it receives a new connection */

  // start advertising
  BLE.advertise();

  Serial.println("Bluetooth® device active, waiting for connections...");
}

void loop() {
  // wait for a Bluetooth® Low Energy central
  BLEDevice central = BLE.central();

  // if a central is connected to the peripheral:
  if (central) {
    Serial.print("Connected to central: ");
    // print the central's BT address:
    Serial.println(central.address());
    // turn on the LED to indicate the connection:
    digitalWrite(LED_BUILTIN, HIGH);

    // check the battery level every 200ms
    // while the central is connected:
    while (central.connected()) {
      long currentMillis = millis();
//      // if 200ms have passed, check the battery level:
      if (currentMillis - previousMillis >= refresh_rate) {
        previousMillis = currentMillis;
        Serial.println("Central connected");
//        Serial.println("going into deep sleep");
//        LowPower.sleep(5000);
//        Serial.println("ended deep sleep");

        updateWeightLevel();
        einkDisplay(1,eink_weight_level,itemNameCharacteristic.value(),itemBinPositionCharacteristic.value()); //  void einkDisplay(int bleConn,int stock, char itemName[],char itemLocation[] )
       }
    }
    // when the central disconnects, turn off the LED:
    digitalWrite(LED_BUILTIN, LOW);
    Serial.print("Disconnected from central: ");
    Serial.println(central.address());

  }
  Serial.println("No Central connected ");
  updateWeightLevel();

  einkDisplay(0,eink_weight_level,itemNameCharacteristic.value(),itemBinPositionCharacteristic.value()); //  void einkDisplay(int bleConn,int stock, char itemName[],char itemLocation[] )
  delay(refresh_rate);
}

void updateWeightLevel() {
  /* Read the current voltage level on the A0 analog input pin.
     This is used here to simulate the charge level of a battery.
  */
  int weightRead = analogRead(A1);
  //int batteryLevel = map(battery, 0, 1023, 0, 100);
  int weightLevel = 0.0088*weightRead*weightRead+0.2676*weightRead+0.3029;
  int weightPercentage = weightLevel*100/itemMaxWeightCharacteristic.value();
  Serial.println(itemNameCharacteristic.value());
  Serial.println(itemBinPositionCharacteristic.value());
  Serial.println(itemMaxWeightCharacteristic.value());
  
  Serial.print("Voltage Level % is now: "); // print it
  Serial.println(weightRead);


  int weightPercentageInt = (int)weightPercentage; //typecast byte into int

  //Serial.println(weightPercentageInt);
    
  if (weightPercentageInt>75) {
    Serial.println("Green");
    digitalWrite(green,HIGH);
    digitalWrite(red,LOW);
    eink_weight_level = 3;

  } else if (weightPercentageInt>25) {
    Serial.println("Yellow");
    digitalWrite(green,HIGH);
    digitalWrite(red,HIGH);
    eink_weight_level = 2;

  } else {
    Serial.println("Red");
    digitalWrite(green,LOW);
    digitalWrite(red,HIGH);
    eink_weight_level = 1;
    //delay(500);
  }
  
  if (weightLevel != oldLevel) {      // if the battery level has changed
    Serial.print("Weight Level % is now: "); // print it
    Serial.println(weightRead);
    weightCharacteristic.writeValue(weightLevel);  // and update the weight characteristic
    levelCharacteristic.writeValue(weightPercentage);  // and update the weight characteristic
    oldLevel = weightLevel;           // save the level for next comparison
  }
}


void einkDisplay_setup()
{
  display.init(115200, true, 2, false); // USE THIS for Waveshare boards with "clever" reset circuit, 2ms reset pulse
  display.setRotation(3);
  display.setFont(&FreeMonoBold9pt7b);
  display.setTextColor(GxEPD_BLACK);
  display.setFullWindow();
  display.firstPage();
}




void einkDisplay(int bleConn,int stock, String itemName,String itemLocation )
{
  
//  display.setRotation(3);
//  display.setFont(&FreeMonoBold9pt7b);
//  display.setTextColor(GxEPD_BLACK);
//  display.setFullWindow();
//  display.firstPage();
  do
  {

//width is 212, height is 104
    display.fillScreen(GxEPD_WHITE);
    display.setCursor(0, 100); //Cursor is set to bottom left corner of text
    if (bleConn==1){
      display.print("BLE Connected");
    } 
    else {
      display.print("BLE Not Connected");
    }
    
    display.setCursor(0, 30);
    display.print("Item: ");
    display.print(itemName);    

    display.setCursor(0, 50);
    display.print("Bin: ");
    display.print(itemLocation);   
    
    display.setCursor(0, 70);
    display.print("Stock: ");

   if (stock == 1){
      display.print("Low");
//    display.fillRect(box_x, box_y, box_w, box_h, GxEPD_BLACK); box_x, box_y are top left corner of box
      display.fillRect(0, 0, display.width(), 15, GxEPD_BLACK); //fill with black to show stock low
//      display.fillRect(0, 0, display.width(), 15, GxEPD_RED); //fill with red to show stock low
    } 
    else if(stock == 2) {
      display.print("Mid");
//    display.fillRect(box_x, box_y, box_w, box_h, GxEPD_BLACK); box_x, box_y are top left corner of box
      display.fillRect(0, 0, display.width(), 15, GxEPD_WHITE); //fill with black to show stock low
    }
    else {
      display.print("High");
//    display.fillRect(box_x, box_y, box_w, box_h, GxEPD_BLACK); box_x, box_y are top left corner of box
      display.fillRect(0, 0, display.width(), 15, GxEPD_WHITE); //fill with black to show stock low
    }

    
    
  }
  while (display.nextPage());
  display.hibernate();
}

I am using the GxEPD2 libary
The arduino nano 33 ble sense is not in the display selection of the GxEPD2_display_selection_new_style.h
It is able to compile on the MKR 1000 but not in the nano

2

Try looking for a example that says how to declare a display.
I think you forgot to declare your display.
Let me know if this helps.

3

I do not know how to declare because the code can compile on the MKR 1000 but not the nano 33 BLE sense, and I suspect there is a pre processed conditional statement for the MKR1000 in the GxEPD2_display_selection_new_style.h but not present for the nano 33 BLE sense. How do I add the statement for the nano 33 BLE sense in?

4

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