Timeout on I2C Write BUSY - not all the time [Adafruit 8x8 matrix backpack]

Gorgeous @allObjects!
it works pretty well, have to try it more.
Sometime pb persisting even with the tries...
I definitively will try with the scotchy diode...

My crappy solution seemed effective but it was an evidence there was a better, nicer code structure to write to do this.

it seems if it catchs an error even with the tries it fail to initialize the display...
never mind i use your "boot sequence"

just a small misspelling throw rather than trow (i'm unfamiliar with this command).

Thanks again.
It's nice code

I do not see a reset command in the doc
therefore i remove the first function (res). ;)

é.

ps: clearInterval() was seen in a forum post about timeout

var ini = function() { // first
  require("Font4x6").add(Graphics);
  // initialisation I2C
  console.log("setup I2C");
  I2C1.setup({scl: B6,sda: B7});
  /* rajouter les init de connexion pour le display */
  console.log("init programme affichage matrice v2.2 - éric choisy ©2019");
  console.log("mém. utilisée: "+Math.round(process.memory().usage/process.memory().total*100)+"%");
}
, osc = function(tries) { if (tries>0) { // third w/ retries
  try { console.log("turn OSC ON");
    digitalPulse(LED2,1,20);//verte
    I2C1.writeTo(0x70, 0x21); // turn on oscillator
    setTimeout(don,250,2);
  } catch(e) { console.log(e);
    setTimeout(osc,250,--tries);
    digitalPulse(LED1,1,20);//rouge
  } } else throw "Unable to turn osc on";
}
, don = function(tries) { if (tries>0) { // fourth w/ retries
  try { console.log("turn display ON");
  digitalPulse(LED2,1,20);//verte
    I2C1.writeTo(0x70, 0x81); // display on
    setTimeout(lum,250,2);
  } catch(e) { console.log(e);
    setTimeout(don,250,--tries);
    digitalPulse(LED1,1,20);// rouge
  } } else throw "Unable to turn display ON";
}
, lum = function(tries) { if (tries>0) { // fifth w/ retries
  try { console.log("set brightness");
    digitalPulse(LED2,1,20);//verte
    I2C1.writeTo(0x70, 0xE0 | 0); // luminosité 0-15
    setTimeout(envoieMatrice, 1000);
  } catch(e) { console.log(e);
    digitalPulse(LED1,1,20);//rouge
    setTimeout(lum,250,--tries);
  } } else throw "Unable to set brightness";
};
const onInit = function() {
  ini();
  osc(3); // starts the chain \:
};

i added led pulse to have visual feedback without a console...