/**
* Set the PWM value based on a position.
*
* This is intended to be used by servos.
*
* @pre SetMaxPositivePwm() called.
* @pre SetMinNegativePwm() called.
*
* @param pos The position to set the servo between 0.0 and 1.0.
*/
void PWM::SetPosition(float pos)
{
if (pos < 0.0)
{
pos = 0.0;
}
else if (pos > 1.0)
{
pos = 1.0;
}
INT32 rawValue;
// note, need to perform the multiplication below as floating point
// before converting to int
rawValue =
(INT32) ((pos * (float)GetFullRangeScaleFactor()) +
GetMinNegativePwm());
wpi_assert((rawValue >= GetMinNegativePwm())
&& (rawValue <= GetMaxPositivePwm()));
wpi_assert(rawValue != kPwmDisabled);
// send the computed pwm value to the FPGA
SetRaw((UINT8) rawValue);
}
/**
* Get the PWM value in terms of a position.
*
* This is intended to be used by servos.
*
* @pre SetMaxPositivePwm() called.
* @pre SetMinNegativePwm() called.
*
* @return The position the servo is set to between 0.0 and 1.0.
*/
float PWM::GetPosition() const {
if (StatusIsFatal()) return 0.0;
int32_t value = GetRaw();
if (value < GetMinNegativePwm()) {
return 0.0;
} else if (value > GetMaxPositivePwm()) {
return 1.0;
} else {
return (float)(value - GetMinNegativePwm()) /
(float)GetFullRangeScaleFactor();
}
}
/**
* Get the PWM value in terms of a position.
*
* This is intended to be used by servos.
*
* @pre SetMaxPositivePwm() called.
* @pre SetMinNegativePwm() called.
*
* @return The position the servo is set to between 0.0 and 1.0.
*/
float PWM::GetPosition()
{
INT32 value = GetRaw();
if (value < GetMinNegativePwm())
{
return 0.0;
}
else if (value > GetMaxPositivePwm())
{
return 1.0;
}
else
{
return (float)(value - GetMinNegativePwm()) / (float)GetFullRangeScaleFactor();
}
}
/**
* Set the PWM value based on a position.
*
* This is intended to be used by servos.
*
* @pre SetMaxPositivePwm() called.
* @pre SetMinNegativePwm() called.
*
* @param pos The position to set the servo between 0.0 and 1.0.
*/
void PWM::SetPosition(float pos) {
if (StatusIsFatal()) return;
if (pos < 0.0) {
pos = 0.0;
} else if (pos > 1.0) {
pos = 1.0;
}
// note, need to perform the multiplication below as floating point before
// converting to int
unsigned short rawValue =
(int32_t)((pos * (float)GetFullRangeScaleFactor()) + GetMinNegativePwm());
// printf("MinNegPWM: %d FullRangeScaleFactor: %d Raw value: %5d Input
//value: %4.4f\n", GetMinNegativePwm(), GetFullRangeScaleFactor(), rawValue,
//pos);
// wpi_assert((rawValue >= GetMinNegativePwm()) && (rawValue <=
//GetMaxPositivePwm()));
wpi_assert(rawValue != kPwmDisabled);
// send the computed pwm value to the FPGA
SetRaw((unsigned short)rawValue);
}