Hello all... first post on here :)
I am very new to Arduino and coding, for the past few days I have been struggling with some code. I am working towards a small Arduino based rover with two DC motor for movement control. Before I build a body and all that fun stuff I wanted to get basic controls working.
With the code below I can move forward, backward and the BR200# and so on... (RB case) all work. When I try BF200# nothing happens.. I thought it might be due to the LOW settings on both motors as the HIGH HIGH works ok.
Anyway I am pretty much lost at this point...
#define PwmPinMotorA 5
#define PwmPinMotorB 6
#define DirectionPinMotorA 3
#define DirectionPinMotorB 2
#define SerialSpeed 9600
#define BufferLength 16
#define LineEnd '#'
char inputBuffer[BufferLength];
void setup()
{
// motor pins must be outputs
pinMode(PwmPinMotorA, OUTPUT);
pinMode(PwmPinMotorB, OUTPUT);
pinMode(DirectionPinMotorA, OUTPUT);
pinMode(DirectionPinMotorB, OUTPUT);
Serial.begin(SerialSpeed);
}
// process a command string
void HandleCommand(char* input, int length)
{
Serial.println(input);
if (length < 2) { // not a valid command
return;
}
int value = 0;
// calculate number following command
if (length > 2) {
value = atoi(&input[2]);
}
int* command = (int*)input;
// check commands
// note that the two bytes are swapped, ie 'RA' means command AR
switch(*command) {
case 'FA':
// motors A & B BACKWARDS
analogWrite(PwmPinMotorA, value);
digitalWrite(DirectionPinMotorA, HIGH);
analogWrite(PwmPinMotorB, value);
digitalWrite(DirectionPinMotorB, LOW);
break;
case 'RA':
// motor A & B FORWARDS
analogWrite(PwmPinMotorA, value);
digitalWrite(DirectionPinMotorA, LOW);
analogWrite(PwmPinMotorB, value);
digitalWrite(DirectionPinMotorB, HIGH);
break;
case 'FB':
// motor A
analogWrite(PwmPinMotorA, value);
digitalWrite(DirectionPinMotorA, LOW);
analogWrite(PwmPinMotorB, value);
digitalWrite(DirectionPinMotorB, LOW);
break;
case 'RB':
// motor B
analogWrite(PwmPinMotorA, value);
digitalWrite(DirectionPinMotorA, HIGH);
analogWrite(PwmPinMotorB, value);
digitalWrite(DirectionPinMotorB, HIGH);
break;
default:
break;
}
}
void loop()
{
// get a command string form the serial port
int inputLength = 0;
do {
while (!Serial.available()); // wait for input
inputBuffer[inputLength] = Serial.read(); // read it in
} while (inputBuffer[inputLength] != LineEnd && ++inputLength < BufferLength);
inputBuffer[inputLength] = 0; // add null terminator
HandleCommand(inputBuffer, inputLength);
}