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IpidReset()

IpidReset() resets the PID integral value and internal state.

void IpidReset(uint8_t id)

Commands

Command	Arguments	Return Value	Operation
`IpidReset(id)`	`uint8_t id` — PID loop number. Supports `0` ~ `255`	`void`	Resets the PID integral value and internal state.

Example

const uint8_t PID_ID = 0;
const float SETPOINT_C = 45.0F;
 
void setup() {
  Serial.begin(115200);
  if (!IpidSet(PID_ID, 2.0F, 0.4F, 0.1F, 100, 0.0F, 100.0F)) return;  // Set PID coefficients, calculation interval and output range.
  IpidItermLimit(PID_ID, -20.0F, 20.0F);  // Limit the minimum and maximum of the PID integral term.
  IpidReverse(PID_ID, false);  // Select direct or reverse PID action.
}
 
void loop() {
  const float temperature = ntcReadf(0);  // Return the NTC 3950 10kΩ sensor temperature as a floating-point value in °C.
  if (IdigitalRead(0, 5)) IpidReset(PID_ID);  // Read the input repeatedly and update only if all samples match. If HIGH and LOW are mixed, retain the previous stable state. / Reset the PID integral value and internal state.
  const float demand = IpidRun(PID_ID, temperature, SETPOINT_C);  // Calculate the PID output from the current value and setpoint.
  const float lastDemand = IpidOutput(PID_ID);  // Return the last calculated PID output value.
  IanalogWritef(0, 0.0F, 100.0F, lastDemand);  // Map the user's floating-point value to the analog output range and output it.
  delay(20);
}

Precautions

PID output can directly affect field equipment. Begin testing with a low output range and small gains.
IpidRun() retains the previous output until the sampleMs interval has elapsed. It may be called repeatedly in loop().
The integral term is automatically constrained by the output limits to reduce windup. Use IpidItermLimit() if additional limits are needed.
The derivative term is calculated from the PV change to reduce abrupt jumps caused by setpoint changes.
IpidReset() resets the integral term, previous PV and previous output value.
Use the same id for only one control loop.

Built-in Commands in the Same Category

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ILOGICS Product Documentation

Table of Contents

IpidReset()

Commands

Example

Precautions

Built-in Commands in the Same Category