Detailed Description

The SROperator is a set dominant flip flop operator, or SR function as referenced by IEC 61131-3 in PLC.

The SROperator output (Q) is set to true on rising edge in the set input (S) and false on rising edge in the reset input (R). If a rising edge is at the same time on both inputs then the set input will dominate and the output will be set to true.

Arguments

When operator is used inside a signal its default input is automatically tied to signal's InternalValue or previous operator's output. Its default output is automatically tied to next operator's input or to signal's Value. See also CDP Operator Usage In CDP Signals.

Example

Below are the example plots for SROperator set input (S, cyan), reset input (R, orange) and output value (Q, yellow).

Actual Processing Code of the SROperator

unsigned int SROperator<bool>::Process()
{
  if (!m_R)
    return STATUS_ERROR;

  if ((bool)*m_S && !m_oldS)
    *m_Q = true;
  else if ((bool)*m_R && !m_oldR)
    *m_Q = false;

  m_oldS = (bool)*m_S;
  m_oldR = (bool)*m_R;
  return STATUS_OK;
}