Sending data from Leonardo to Android via bluetooth

Projects Programming
1

Hi guys!
i have a few question for you.

This is an example of code which allow arduino to read data sended from android via bluetooth.

void loop() {
 
  if(Serial1.available() > 0){ 
      state = Serial1.read(); }
        
  if (state == '3') {
      digitalWrite(EngineON, HIGH);}   //digital pin (relay)
}

but... tell me how it should look like if i would like to SEND same data via bluetooth to android ? do i need any additional libraries ?
im asking because i have configurated temperature sensor everythink works fine in "Serial Port Monitor" but i would like to SEND teperature from arduino to android.

i really need your hint.

2

tell me how it should look like if i would like to SEND same data via bluetooth to android ?

If Serial1 is connected to the bluetooth device, and available() and read() get data from it, then write(), print(), and println() send data to it.

3

just like that? :

void loop() {
 
  if(Serial1.available() > 0){ 
      state = Serial1.read(); }
      sensors.requestTemperatures();
      Serial.print(sensors.getTempCByIndex(0));
      temp = sensors.getTempCByIndex(0);
      write(temp);

 if (state == '3') {
      digitalWrite(EngineON, HIGH);}
}
4

just like that?

No. Properly formatted for one thing.

      sensors.requestTemperatures();
      Serial.print(sensors.getTempCByIndex(0));
      temp = sensors.getTempCByIndex(0);
      write(temp);

What does write() do? Is that supposed to be Serial1.write()? If so, why do you want to use both print() (send a string) and write() (send binary data)?

Why are you calling getTempCByIndex() twice?

5

PaulS:
Why are you calling getTempCByIndex() twice?

Only to make sure that it works fine in arduino. it will be deleted in final version :slight_smile:

so the only one error is that i wrote write(temp); instead Serial1.write(temp) ?
Am i able to send this as a string to easly display it in android app ?
which way is better , to send temp as string or binary data ?

sorry for newbie questions but iam beginner... with interesting idea creating on-board computer in my car fiat 126p.

6

Am i able to send this as a string to easly display it in android app ?

Send me your Arduino and your phone, and I'll test it for you.

which way is better , to send temp as string or binary data ?

Depends on what you are going to do with the data.

7

Send me your Arduino and your phone, and I'll test it for you.

im creating android app in app inventor its in *.aia extension , its ok ? but I do not have a code sequence which should be responsible for displaying the temp. arduino app is done so i will send both on pw, ok ?

Depends on what you are going to do with the data.

i just want to display it :slight_smile: beacuse arduino does all the calcullation.