Hi, I have 2 HC-05 modules and decided to have one in a controller with 2 joysticks and the other one in a circuit with 4 DC-Motors. Once they are connected and I try to move the joysticks, nothing happends. This is my code: Controller: #include SoftwareSerial MANDO (10, 11); int yPin = A0; int yVal; int yPin2 = A2; int yVal2; int xPin = A1; int xVal; void setup() { // put your setup code here, to run once: Serial.begin (9600); Serial.println ("Listo"); MANDO.begin (38400); pinMode(yPin, INPUT); pinMode(yPin2, INPUT); pinMode(xPin, INPUT); } void loop() { // put your main code here, to run repeatedly: yVal = analogRead(yPin); //Serial.println(yVal); yVal2 = analogRead(yPin2); //Serial.println(yVal2); xVal = analogRead(xPin); //Serial.println(xVal); if (MANDO.available()) { //Serial.write(MANDO.read()); Serial.write(yVal); Serial.write(yVal2); Serial.write(xVal); } } The cicuit with the 4 DC Motors: #include SoftwareSerial SUBMARINO (2, 3); int speedPin = 9; int dirPin1 = 8; int dirPin2 = 7; int speedMotor; int yVal; //motor izquierdo int speedPin2 = 6; int dirPin4 = 5; int dirPin3 = 4; int speedMotor2; int yVal2; int xVal; //motor derecho int speedPin3 = 10; int dirPin5 = 11; int dirPin6 = 12; int speedMotor3; int state = 20; void setup() { // put your setup code here, to run once: Serial.begin (9600); Serial.println ("Listo"); SUBMARINO.begin (38400); pinMode(speedPin, OUTPUT); pinMode(dirPin1, OUTPUT); pinMode(dirPin2, OUTPUT); pinMode(speedPin2, OUTPUT); pinMode(speedPin2, OUTPUT); pinMode(dirPin3, OUTPUT); pinMode(dirPin4, OUTPUT); pinMode(speedPin3, OUTPUT); pinMode(dirPin5, OUTPUT); pinMode(dirPin6, OUTPUT); } void loop() { // put your main code here, to run repeatedly: digitalWrite(dirPin1, 0); digitalWrite(dirPin2, 0); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 0); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 0); if (SUBMARINO.available()) { //Serial.write(SUBMARINO.read()); yVal = Serial.read(); Serial.write(yVal); yVal2 = Serial.read(); Serial.write(yVal2); xVal = Serial.read(); Serial.write(xVal); if (yVal > 600) { speedMotor = map(yVal,600,1023,0,255); digitalWrite(dirPin1, 0); digitalWrite(dirPin2, 1); analogWrite(speedPin, speedMotor); } if (yVal 400 && yVal 400 && yVal2 600) { speedMotor2 = map(yVal2,600,1023,0,255); speedMotor3 = map(yVal2,600,1023,0,255); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 1); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 1); analogWrite(speedPin2, speedMotor2); analogWrite(speedPin3, speedMotor3); } if (yVal2 400 && xVal 600) { speedMotor2 = map(xVal,600,1023,0,255); speedMotor3 = map(xVal,600,1023,0,255); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 1); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 0); analogWrite(speedPin2, speedMotor2); analogWrite(speedPin3, speedMotor3); } if (xVal < 400) { speedMotor2 = map(xVal,400,0,0,255); speedMotor3 = map(xVal,400,0,0,255); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 0); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 1); analogWrite(speedPin2, speedMotor2); analogWrite(speedPin3, speedMotor3); } } } Does anyone know were the problem is? Thanks.

[image] lex_212: After making those changes, it finally sends the data to the other board That´s a good progress! :slightly_smiling_face: [image] lex_212: the board does not distinguish between the 3 variables So it´s time to do one of these things: a) identify the data that you´re sending in order to know what you´re receiving. For example, defining yVal as 1, then sending (1,value of yVal) . Doing the same for yVal2 and xVal using, of course, different numbers to identify them; or b) instead of sending separated values, send all of them in a row (yVal, yVal2, xVal).

How could I define the variables as numbers? Using #define? Beacuse when I do this: #define yVal 0 #define yVal2 1 #define xVal 2 An error while compiling says: expected unqualified-id before numeric constant

Post the whole code. The error is not in those 3 lines. Please include the entire error message. It is easy to do. There is a button (lower right of the IDE window) called "copy error message". Copy the error and paste into a post in code tags. Paraphrasing the error message leaves out important information.

Arduino: 1.8.16 (Windows 10), Board: "Arduino Uno" BluetoothPrueba:2:14: error: expected unqualified-id before numeric constant #define yVal 0 ^ C:\Users\aleja\Desktop\BluetoothPrueba\BluetoothPrueba.ino:9:5: note: in expansion of macro 'yVal' int yVal; ^~~~ BluetoothPrueba:3:15: error: expected unqualified-id before numeric constant #define yVal2 1 ^ C:\Users\aleja\Desktop\BluetoothPrueba\BluetoothPrueba.ino:12:5: note: in expansion of macro 'yVal2' int yVal2; ^~~~~ BluetoothPrueba:4:14: error: expected unqualified-id before numeric constant #define xVal 2 ^ C:\Users\aleja\Desktop\BluetoothPrueba\BluetoothPrueba.ino:15:5: note: in expansion of macro 'xVal' int xVal; ^~~~ C:\Users\aleja\Desktop\BluetoothPrueba\BluetoothPrueba.ino: In function 'void loop()': BluetoothPrueba:30:25: error: lvalue required as left operand of assignment yVal = analogRead(yPin); ^ BluetoothPrueba:32:27: error: lvalue required as left operand of assignment yVal2 = analogRead(yPin2); ^ BluetoothPrueba:34:25: error: lvalue required as left operand of assignment xVal = analogRead(xPin); ^ BluetoothPrueba:46:20: error: call of overloaded 'write(int)' is ambiguous MANDO.write(0); ^ In file included from C:\Users\aleja\Desktop\BluetoothPrueba\BluetoothPrueba.ino:1:0: C:\Users\aleja\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.4\libraries\SoftwareSerial\src/SoftwareSerial.h:102:18: note: candidate: virtual size_t SoftwareSerial::write(uint8_t) virtual size_t write(uint8_t byte); ^~~~~ In file included from C:\Users\aleja\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.4\cores\arduino/Stream.h:26:0, from C:\Users\aleja\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.4\cores\arduino/HardwareSerial.h:29, from C:\Users\aleja\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.4\cores\arduino/Arduino.h:233, from sketch\BluetoothPrueba.ino.cpp:1: C:\Users\aleja\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.8.4\cores\arduino/Print.h:52:12: note: candidate: size_t Print::write(const char*) size_t write(const char *str) { ^~~~~ exit status 1 expected unqualified-id before numeric constant This report would have more information with "Show verbose output during compilation" option enabled in File -> Preferences. This is the code: #include #define yVal 0 #define yVal2 1 #define xVal 2 SoftwareSerial MANDO (10, 11); int yPin = A0; int yVal; int yPin2 = A1; int yVal2; int xPin = A2; int xVal; void setup() { // put your setup code here, to run once: Serial.begin (9600); Serial.println ("Listo"); MANDO.begin (38400); pinMode(yPin, INPUT); pinMode(yPin2, INPUT); pinMode(xPin, INPUT); } void loop() { // put your main code here, to run repeatedly: yVal = analogRead(yPin); //Serial.println(yVal); yVal2 = analogRead(yPin2); //Serial.println(yVal2); xVal = analogRead(xPin); //Serial.println(xVal); if (yVal > 600 || yVal 600 || yVal2 600 || xVal < 400) { MANDO.write(2); } }

[image] lex_212: How could I define the variables as numbers? Using #define? Nope, forget the #defines. I was suggesting something like this: void loop() { // put your main code here, to run repeatedly: yVal = analogRead(yPin); //Serial.println(yVal); yVal2 = analogRead(yPin2); //Serial.println(yVal2); xVal = analogRead(xPin); //Serial.println(xVal); if (yVal > 600 || yVal 600 || yVal2 600 || xVal < 400) { MANDO.write(3); MANDO.write(","); MANDO.write(xVal); } } And then you have to adapt your receiver code to "understand" that if you´re receiving "1" before the value, you´re talking about yVal. If you´re receiving "2" you´re talking about yVal2. And if you´re receiving "3", you´re talking about xVal. This is only a suggestion. The funny thing on developing things is exactly the challenge to find solutions to your problems. :wink:

Ok, I changed the one of the scripts to this: #include SoftwareSerial SUBMARINO (2, 3); int speedPin = 9; int dirPin1 = 8; int dirPin2 = 7; int speedMotor; int yVal; //motor izquierdo int speedPin2 = 6; int dirPin4 = 5; int dirPin3 = 4; int speedMotor2; int yVal2; int xVal; //motor derecho int speedPin3 = 10; int dirPin5 = 11; int dirPin6 = 12; int speedMotor3; char bt = 0; void setup() { // put your setup code here, to run once: Serial.begin (9600); Serial.println ("Listo"); SUBMARINO.begin (38400); pinMode(speedPin, OUTPUT); pinMode(dirPin1, OUTPUT); pinMode(dirPin2, OUTPUT); pinMode(speedPin2, OUTPUT); pinMode(speedPin2, OUTPUT); pinMode(dirPin3, OUTPUT); pinMode(dirPin4, OUTPUT); pinMode(speedPin3, OUTPUT); pinMode(dirPin5, OUTPUT); pinMode(dirPin6, OUTPUT); } void loop() { // put your main code here, to run repeatedly: digitalWrite(dirPin1, 0); digitalWrite(dirPin2, 0); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 0); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 0); if (SUBMARINO.available()) { bt = SUBMARINO.read(); //Serial.write(SUBMARINO.read()); yVal = SUBMARINO.read(); Serial.write(yVal); yVal2 = SUBMARINO.read(); Serial.write(yVal2); xVal = SUBMARINO.read(); Serial.write(xVal); if (yVal > 600 && bt == 1) { speedMotor = map(yVal,600,1023,0,255); digitalWrite(dirPin1, 0); digitalWrite(dirPin2, 1); analogWrite(speedPin, speedMotor); } if (yVal 400 && yVal 400 && yVal2 600 && bt == 2) { speedMotor2 = map(yVal2,600,1023,0,255); speedMotor3 = map(yVal2,600,1023,0,255); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 1); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 1); analogWrite(speedPin2, speedMotor2); analogWrite(speedPin3, speedMotor3); } if (yVal2 400 && xVal 600 && bt == 3) { speedMotor2 = map(xVal,600,1023,0,255); speedMotor3 = map(xVal,600,1023,0,255); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 1); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 0); analogWrite(speedPin2, speedMotor2); analogWrite(speedPin3, speedMotor3); } if (xVal < 400 && bt == 3) { speedMotor2 = map(xVal,400,0,0,255); speedMotor3 = map(xVal,400,0,0,255); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 0); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 1); analogWrite(speedPin2, speedMotor2); analogWrite(speedPin3, speedMotor3); } } /*if (Serial.available()) SUBMARINO.write(Serial.read()); yVal = SUBMARINO.read(); SUBMARINO.write(yVal); yVal2 = SUBMARINO.read(); SUBMARINO.write(yVal2); xVal = SUBMARINO.read(); SUBMARINO.write(xVal);*/ } And this is the code of the controller: #include SoftwareSerial MANDO (10, 11); int yPin = A0; int yVal; int yPin2 = A1; int yVal2; int xPin = A2; int xVal; void setup() { // put your setup code here, to run once: Serial.begin (9600); Serial.println ("Listo"); MANDO.begin (38400); pinMode(yPin, INPUT); pinMode(yPin2, INPUT); pinMode(xPin, INPUT); } void loop() { // put your main code here, to run repeatedly: yVal = analogRead(yPin); //Serial.println(yVal); yVal2 = analogRead(yPin2); //Serial.println(yVal2); xVal = analogRead(xPin); //Serial.println(xVal); if (yVal > 600 || yVal 600 || yVal2 600 || xVal < 400) { MANDO.write(3); MANDO.write(","); MANDO.write(xVal); } } It know distinguishes between the 3 values, but it has two problems: It only works one way, it doesn's matter which way I move the joysticks, the motors move the same way. The motors move like if they were blinking, they move very slowly and , and the lights of the l298 modules are, in fact, blinking.

Some comments: a) the controller is only sending values that are more than 600 or less than 400. There´s no chance of the receiver to get values between 400 and 600. So, these parts of the receiver code are actually doing nothing: if (yVal > 400 && yVal 400 && yVal2 400 && xVal 400 && xVal < 600 && bt == 3) like this: if (400 < xVal < 600 && bt == 3) ? c) if (yVal <= 400 && bt == 1) { speedMotor = map(yVal,400,0,0,255); this is doing an inverting map (the less yVal becomes when lower than 400, the higher motor speed gets). I believe that this the desired effect, right? d) void loop() { // put your main code here, to run repeatedly: digitalWrite(dirPin1, 0); digitalWrite(dirPin2, 0); digitalWrite(dirPin3, 0); digitalWrite(dirPin4, 0); digitalWrite(dirPin5, 0); digitalWrite(dirPin6, 0); This part of the loop is turning off the motors at each iteraction of the code and can be the cause of what you describe in (2). Shouldn´t it be on the setup?

Didn't thought about what you say on d), because it worked perfectly before using blueooth, I didn't thought about that being the problem. I will try that as soon as I can. Also what you say on c) is right, I want the motor to increase its velocity the less the joysitkcs values is lower 400, the higher the motor gets, but I want that when the jostick value is higher than 600, it spins in the opposite direction.

You are making things difficult by not following the methods of the previously linked Serial Input Basics. For example on the sending code, MANDO.write() will only send a byte value and not an integer. You will only send the low byte value of the numbers between 400 and 600. if (yVal > 600 || yVal <= 400) { MANDO.write(1); MANDO.write(","); MANDO.write(yVal); } As well, this receiving code makes no sense for the number of bytes being sent. if (SUBMARINO.available()) { bt = SUBMARINO.read(); //Serial.write(SUBMARINO.read()); yVal = SUBMARINO.read(); Serial.write(yVal); yVal2 = SUBMARINO.read(); Serial.write(yVal2); xVal = SUBMARINO.read(); Serial.write(xVal);

Connect two HC-05 modules to controll DC Motors with joysticks

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The Serial Input Basics tutorial with show you several methods to arrange, send, and receive the data.

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Connect two HC-05 modules to controll DC Motors with joysticks

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