Hi all,
I have designed a keyboard on the M5Paper to type in letters and to display the content on the ePaper display. Currently I use "canvas.pushCanvas(0,0,UPDATE_MODE_DU4);" which seems to me to be the fastest update mode.

However when I type in the letters, I still have to wait "too long" until the display is updated.

What can you recommend being the fastest way to display the new letters? Is there a possibility to partially update the display? I tried "M5.EPD.UpdateArea(0,60,540,400,UPDATE_MODE_GL16);" but nothing changes.

Thanks.

DiWa

CODE (needful part of it):

void Tastatur(){
canvas.fillCanvas(0);
Header();
canvas.setTextArea(10, 60, 520, 460);
canvas.setTextSize(48);
canvas.print(Eingabe);

//Raster
canvas.setTextSize(32);
canvas.drawRoundRect( 10, 430, 168, 80, 10, 15);
canvas.drawRoundRect(186, 430, 168, 80, 10, 15);
canvas.drawRoundRect(362, 430, 168, 80, 10, 15);
canvas.fillRoundRect( 11, 431, 166, 78, 9, 2);
canvas.fillRoundRect(187, 431, 166, 78, 9, 2);
canvas.fillRoundRect(363, 431, 166, 78, 9, 2);
canvas.drawString("wiki", 65, 455);
canvas.drawString("wo", 250, 455);
canvas.drawString("123", 415, 455);

//canvas.createRender(48, 256);
canvas.setTextSize(48);
canvas.drawRoundRect( 10, 518, 80, 80, 10, 15); canvas.drawString("a", 35, 538);
canvas.drawRoundRect( 98, 518, 80, 80, 10, 15); canvas.drawString("b", 123, 538);
canvas.drawRoundRect(186, 518, 80, 80, 10, 15); canvas.drawString("c", 211, 538);
canvas.drawRoundRect(274, 518, 80, 80, 10, 15); canvas.drawString("d", 299, 538);
canvas.drawRoundRect(362, 518, 80, 80, 10, 15); canvas.drawString("e", 387, 538);
canvas.drawRoundRect(450, 518, 80, 80, 10, 15); canvas.drawString("f", 475, 538);
canvas.drawRoundRect( 10, 606, 80, 80, 10, 15); canvas.drawString("g", 35, 626);
canvas.drawRoundRect( 98, 606, 80, 80, 10, 15); canvas.drawString("h", 123, 626);
canvas.drawRoundRect(186, 606, 80, 80, 10, 15); canvas.drawString("i", 216, 626);
canvas.drawRoundRect(274, 606, 80, 80, 10, 15); canvas.drawString("j", 305, 626);
canvas.drawRoundRect(362, 606, 80, 80, 10, 15); canvas.drawString("k", 387, 626);
canvas.drawRoundRect(450, 606, 80, 80, 10, 15); canvas.drawString("l", 475, 626);
canvas.drawRoundRect( 10, 694, 80, 80, 10, 15); canvas.drawString("m", 33, 714);
canvas.drawRoundRect( 98, 694, 80, 80, 10, 15); canvas.drawString("n", 123, 714);
canvas.drawRoundRect(186, 694, 80, 80, 10, 15); canvas.drawString("o", 211, 714);
canvas.drawRoundRect(274, 694, 80, 80, 10, 15); canvas.drawString("p", 299, 714);
canvas.drawRoundRect(362, 694, 80, 80, 10, 15); canvas.drawString("q", 387, 714);
canvas.drawRoundRect(450, 694, 80, 80, 10, 15); canvas.drawString("r", 475, 714);
canvas.drawRoundRect( 10, 782, 80, 80, 10, 15); canvas.drawString("s", 35, 802);
canvas.drawRoundRect( 98, 782, 80, 80, 10, 15); canvas.drawString("t", 123, 802);
canvas.drawRoundRect(186, 782, 80, 80, 10, 15); canvas.drawString("u", 211, 802);
canvas.drawRoundRect(274, 782, 80, 80, 10, 15); canvas.drawString("v", 299, 802);
canvas.drawRoundRect(362, 782, 80, 80, 10, 15); canvas.drawString("w", 387, 802);
canvas.drawRoundRect(450, 782, 80, 80, 10, 15); canvas.drawString("x", 475, 802);
canvas.drawRoundRect( 10, 870, 80, 80, 10, 15); canvas.drawString("y", 35, 890);
canvas.drawRoundRect( 98, 870, 80, 80, 10, 15); canvas.drawString("z", 123, 890);
canvas.drawRoundRect(186, 870, 80, 80, 10, 15); canvas.drawString("?", 211, 890);

canvas.drawRoundRect(275, 870, 80, 80, 10, 15); canvas.fillRoundRect(276, 871, 78, 78, 9, 2); canvas.drawString("_", 305, 890);
canvas.drawRoundRect(362, 870, 80, 80, 10, 15); canvas.fillRoundRect(363, 871, 78, 78, 9, 2); canvas.drawString("<-", 375, 890);
canvas.drawRoundRect(450, 870, 80, 80, 10, 15); canvas.fillRoundRect(451, 871, 78, 78, 9, 2); canvas.drawString("OK", 455, 890);

canvas.pushCanvas(0,0,UPDATE_MODE_GC16);

int touch = 0;
int Auswahl = 0;
int Leer_Stelle = 0;
int Zeichen = 0;

while(Auswahl == 0){
if(M5.TP.avaliable()){
if(!M5.TP.isFingerUp()){
M5.TP.update();
bool is_update = false;
for(int i=0;i<2; i++){
tp_finger_t FingerItem = M5.TP.readFinger(i);
if((point[i][0]!=FingerItem.x)||(point[i][1]!=FingerItem.y)){
is_update = true;
point[i][0] = FingerItem.x;
point[i][1] = FingerItem.y;
if (FingerItem.x >= 430 && FingerItem.x < 510 && FingerItem.y >= 360 && FingerItem.y <= 530) {
Serial.println("wiki");
canvas.setTextSize(32);
Eingabe = "Schreib einen wiki\nArtikel über\n";
canvas.pushCanvas(0,0,UPDATE_MODE_DU4);
}
if (FingerItem.x >= 430 && FingerItem.x < 510 && FingerItem.y >= 274 && FingerItem.y <= 352) {
Serial.println("wo");
canvas.setTextSize(32);
Eingabe = "wo finde ich ";
canvas.pushCanvas(0,0,UPDATE_MODE_GC16);
}
if (FingerItem.x >= 430 && FingerItem.x < 510 && FingerItem.y >= 98 && FingerItem.y <= 178) {
Serial.println("123");
Sonderzeichen();
}
if (FingerItem.x >= 518 && FingerItem.x < 598 && FingerItem.y >= 450 && FingerItem.y <= 530) Eingabe = Eingabe + "a"; //Serial.print("a");
if (FingerItem.x >= 518 && FingerItem.x < 598 && FingerItem.y >= 362 && FingerItem.y <= 442) Eingabe = Eingabe + "b"; //Serial.print("b");
if (FingerItem.x >= 518 && FingerItem.x < 598 && FingerItem.y >= 274 && FingerItem.y <= 352) Eingabe = Eingabe + "c"; //Serial.print("c");
if (FingerItem.x >= 518 && FingerItem.x < 598 && FingerItem.y >= 186 && FingerItem.y <= 266) Eingabe = Eingabe + "d"; //Serial.print("d");
if (FingerItem.x >= 518 && FingerItem.x < 598 && FingerItem.y >= 98 && FingerItem.y <= 178) Eingabe = Eingabe + "e"; //Serial.print("e");
if (FingerItem.x >= 518 && FingerItem.x < 598 && FingerItem.y >= 10 && FingerItem.y <= 90) Eingabe = Eingabe + "f"; //Serial.print("f");
if (FingerItem.x >= 606 && FingerItem.x < 686 && FingerItem.y >= 450 && FingerItem.y <= 530) Eingabe = Eingabe + "g"; //Serial.print("g");
if (FingerItem.x >= 606 && FingerItem.x < 686 && FingerItem.y >= 362 && FingerItem.y <= 442) Eingabe = Eingabe + "h"; //Serial.print("h");
if (FingerItem.x >= 606 && FingerItem.x < 686 && FingerItem.y >= 274 && FingerItem.y <= 352) Eingabe = Eingabe + "i"; //Serial.print("i");
if (FingerItem.x >= 606 && FingerItem.x < 686 && FingerItem.y >= 186 && FingerItem.y <= 266) Eingabe = Eingabe + "j"; //Serial.print("j");
if (FingerItem.x >= 606 && FingerItem.x < 686 && FingerItem.y >= 98 && FingerItem.y <= 178) Eingabe = Eingabe + "k"; //Serial.print("k");
if (FingerItem.x >= 606 && FingerItem.x < 686 && FingerItem.y >= 10 && FingerItem.y <= 90) Eingabe = Eingabe + "l"; //Serial.print("l");
if (FingerItem.x >= 694 && FingerItem.x < 774 && FingerItem.y >= 450 && FingerItem.y <= 530) Eingabe = Eingabe + "m"; //Serial.print("m");
if (FingerItem.x >= 694 && FingerItem.x < 774 && FingerItem.y >= 362 && FingerItem.y <= 442) Eingabe = Eingabe + "n"; //Serial.print("n");
if (FingerItem.x >= 694 && FingerItem.x < 774 && FingerItem.y >= 274 && FingerItem.y <= 352) Eingabe = Eingabe + "o"; //Serial.print("o");
if (FingerItem.x >= 694 && FingerItem.x < 774 && FingerItem.y >= 186 && FingerItem.y <= 266) Eingabe = Eingabe + "p"; //Serial.print("p");
if (FingerItem.x >= 694 && FingerItem.x < 774 && FingerItem.y >= 98 && FingerItem.y <= 178) Eingabe = Eingabe + "q"; //Serial.print("q");
if (FingerItem.x >= 694 && FingerItem.x < 774 && FingerItem.y >= 10 && FingerItem.y <= 90) Eingabe = Eingabe + "r"; //Serial.print("r");
if (FingerItem.x >= 782 && FingerItem.x < 862 && FingerItem.y >= 450 && FingerItem.y <= 530) Eingabe = Eingabe + "s"; //Serial.print("s");
if (FingerItem.x >= 782 && FingerItem.x < 862 && FingerItem.y >= 362 && FingerItem.y <= 442) Eingabe = Eingabe + "t"; //Serial.print("t");
if (FingerItem.x >= 782 && FingerItem.x < 862 && FingerItem.y >= 274 && FingerItem.y <= 352) Eingabe = Eingabe + "u"; //Serial.print("u");
if (FingerItem.x >= 782 && FingerItem.x < 862 && FingerItem.y >= 186 && FingerItem.y <= 266) Eingabe = Eingabe + "v"; //Serial.print("v");
if (FingerItem.x >= 782 && FingerItem.x < 862 && FingerItem.y >= 98 && FingerItem.y <= 178) Eingabe = Eingabe + "w"; //Serial.print("w");
if (FingerItem.x >= 782 && FingerItem.x < 862 && FingerItem.y >= 10 && FingerItem.y <= 90) Eingabe = Eingabe + "x"; //Serial.print("x");
if (FingerItem.x >= 870 && FingerItem.x < 950 && FingerItem.y >= 450 && FingerItem.y <= 530) Eingabe = Eingabe + "y"; //Serial.print("y");
if (FingerItem.x >= 870 && FingerItem.x < 950 && FingerItem.y >= 362 && FingerItem.y <= 442) Eingabe = Eingabe + "z"; //Serial.print("z");
if (FingerItem.x >= 870 && FingerItem.x < 950 && FingerItem.y >= 274 && FingerItem.y <= 352) Eingabe = Eingabe + "?"; //Serial.print("z");
if (FingerItem.x >= 870 && FingerItem.x < 950 && FingerItem.y >= 186 && FingerItem.y <= 266) { //Serial.print("Leer");
Eingabe = Eingabe + " ";
Leer_Stelle = Eingabe.length() - 1;
}
if (FingerItem.x >= 870 && FingerItem.x < 950 && FingerItem.y >= 98 && FingerItem.y <= 178) { //Serial.print("<-");
Eingabe_len = Eingabe.length();
if (Eingabe_len >= 1) Eingabe = Eingabe.substring(0, Eingabe_len - 1);
canvas.fillRect(0, 52, 540, 360, 0);
}
if (FingerItem.x >= 870 && FingerItem.x < 950 && FingerItem.y >= 10 && FingerItem.y <= 90) {
Auswahl = 1;
Serial.println("OK"); Serial.println();
}
int Zeilenlaenge = 20;
canvas.setTextSize(48);
canvas.setTextArea(10, 60, 520, 460);
Zeichen = Zeichen + 1;
if (Zeichen > Zeilenlaenge){
Eingabe.setCharAt(Leer_Stelle, '\n');
canvas.fillRect(0, 60, 540, 360, 0);
Zeichen = Eingabe.length() - Leer_Stelle;
}
canvas.print(Eingabe);
canvas.pushCanvas(0,0,UPDATE_MODE_DU4);
}
}
}
}
}
Eingabe.replace('\n', ' ');
Serial.println(Eingabe);
monitorWiFi();
canvas.setTextArea(10, 60, 520, 460);
canvas.drawRect(100, 300, 330, 80, 15); canvas.fillRect(101, 301, 328, 78, 2);
canvas.drawString("processing ...", 110, 320);
canvas.pushCanvas(0,0,UPDATE_MODE_GL16);
Serial.println(openAI_text(Eingabe));
}

Link to hackster.io

To ease reading the recipe while cooking, the M5Paper hangs on the cooker hood (my fridge is not magnetic unfortunately) and shows the recipe's details on its ePaper display.

All recipes are managed in the Recipe Keeper app, and the information about ingredients and preparation is sent via Telegram API to M5Paper.

More in the video, if you are interested: https://youtu.be/hrmYldbOStQ

In case you are interested about the final result: https://youtu.be/hrmYldbOStQ

Solved, this works fine:

char Rezept[50] = "Line 1 \n Line 2";

and

canvas.print(Rezept);

I am trying to display a longer text received from Telegram on the M5Paper display. The text includes \n for line breaks, however I am unable to display it properly. This is the snippit from the Arduino code:

String Rezept = "Line 1 \n Line 2";

void setup() {
Serial.begin(115200);
M5.begin();
M5.EPD.SetRotation(90);
M5.EPD.Clear(true);

canvas.createCanvas(540, 960);
canvas.setTextSize(3);
canvas.setTextArea(0, 0, 760, 390);
canvas.setTextWrap(true, false);
canvas.printf(Rezept, 35, 350);
canvas.printf("Line 1 \n Line 2", 35, 350);
canvas.drawString("Line 1 \n Line 2", 35, 350);
canvas.pushCanvas(0,0,UPDATE_MODE_DU4);

I tried different methods, but none works:
canvas.printf(Rezept, 35, 350); --> no matching function for call to 'M5EPD_Canvas::println(String&, int, int)'
canvas.printf("Line 1 \n Line 2", 35, 350); --> This works well, but I hard coded text
canvas.drawString("Line 1 \n Line 2", 35, 350); --> does not recognize the \n

Any idea what I can do? Thanks a lot!