Set a switch on until a flag is reached and then set the switch to off - c

Question

What would be the best and easiest(simplest) way to do this..?
I am writing code in C or Capel (Vector CANoe)
I have a switch on a panel which I have designed in Vector CANoe , turns a motor on and off (0 == off and 1 == on) and I want to turn the motor off when it reaches its limit .. to stop the motor burning out ! (we know it has reached its limit when the a sensor says that the limit is reached (sensor = 1 for limit reached and 0 for not reached)
How would I do this?
i want to do something like this
WHILE (clutchMotorPower==1 & sensorClutchDisengaged !=1)
break;
else clutchMotorPower==0
WHILE (clutchMotorPower==1 & sensorClutchEngaged !=1)
break;
else clutchMotorPower==0

Answer 1

I don't know much about the system you're working on, so this is going to be some bare-bones code. Anyway, let's go through this step-by-step.
Assumptions:
button is a variable that is 1 if the button is currently pressed and 0 otherwise.
motor is a variable that we set to 1 to turn the motor on, or 0 to turn it off.
sensor is a variable that is 1 when the sensor is activated, or 0 otherwise
First, we need code to toggle the motor state when the button is pressed. (Assume all code samples are inside a function called from your main loop)
//values of static variables are preserved between function calls
static char bActivateMotor = 0; //1 if we should activate motor, 0 otherwise
static char bButtonHeld = 0; //1 if button was pressed last loop
//(to differentiate between button being held and it being released and pressed again)
if(!button) {
bButtonHeld = 0; //if button is not being pressed, it can't be being held down.
}
if(!bActivateMotor) { //we aren't running the motor
if(button && !bButtonHeld) { //button was pressed this loop (not held from previous loop)
bButtonHeld = 1; //Don't toggle motor state next loop just because button was held down
bActivateMotor = 1; //we should be running the motor
}
else {
motor = 0;
}
}
if(bActivateMotor) { //not else because could be activated this loop
if(button && !bButtonHeld) { //button toggles motor; if we're running, stop.
bButtonHeld = 1;
bActivateMotor = 0;
}
else {
motor = 1;
}
}
Now, the next part is to stop the motor when the sensor has activated:
//values of static variables are preserved between function calls
static char bActivateMotor = 0; //1 if we should activate motor, 0 otherwise
static char bButtonHeld = 0; //1 if button was pressed last loop
//(to differentiate between button being held and it being released and pressed again)
if(!button) {
bButtonHeld = 0; //if button is not being pressed, it can't be being held down.
}
if(!bActivateMotor) { //we aren't running the motor
if(button && !bButtonHeld) { //button was pressed this loop (not held from previous loop)
bButtonHeld = 1; //Don't toggle motor state next loop just because button was held down
bActivateMotor = 1; //we should be running the motor
}
else {
motor = 0;
}
}
if(bActivateMotor) { //not else because could be activated this loop
if(button && !bButtonHeld) { //button toggles motor; if we're running, stop.
bButtonHeld = 1;
bActivateMotor = 0;
}
/////////////////////
// Added Code Here //
/////////////////////
else if(sensor) {
bActivateMotor = 0; //motor will shut off next loop
}
else {
motor = 1;
}
}
With the lack of specifics about your code, it's hard to figure out exactly what difficulties you might be having, but hopefully the algorithm above will be a good starting point.