void sendMsg(const String& msg) {
guioCharacteristic.writeValue(msg);
delay(50);
}

delay(50) is a limit causing 2 differents problems :

• no more than 20 msg/second
• program is inoperative during all this time in delay()

I would like to fill a chartwith 64 or 128 values, each second, so I tried to reduce the delai time, but results are erratics.

Can somebody explain me the reasons ?

Further more, I've used Bluetooth classic with an HC05 and it was working well at 19200 bds.

Sorry for my poor english !!