dpSetAndWaitForValue()

This function is a combination of the functions dpSet() and dpWaitForValue().

Synopsis

int dpSetAndWaitForValue(dyn_string dpNamesSet, dyn_anytype dpValuesSet,

dyn_string dpNamesWait, dyn_anytype conditions, dyn_string dpNamesReturn, dyn_anytype &returnValues, time timeout [,bool &timeExpired]);

Parameters

Parameter Description
dpNamesSet The datapoint attribute a value is assigned to.
dpValuesSet The value that is assigned to the datapoint attribute.
dpNamesWait A datapoint list that is compared to the values of conditions.
conditions Target values of arbitrary type and number. The values must correspond to the dp list dpNamesWait. The function waits for a value change that fulfills the conditions.
dpNamesReturn DP list whose values are returned. dpNamesWait and dpNamesReturn can contain same DPs.
returnValues Values that are returned from the list dpNamesReturn via dpSet().
timeout A time interval that specifies how long the function waits for the conditions to be fulfilled. The value 0 means that the function never expires.
timeExpired Optional parameter that is set to TRUE when the function expires (see timeout above).

Return Value

In the event of an error -1, otherwise 0

Errors

Errors can be retrieved with getLastError(). An error message is issued in the event of missing or incorrect arguments.

Description

The function triggers a verify function and subsequently sets values according to the dpSet function. The function returns back like the function dpWaitForValue() first when either the condition is fulfilled (this can be fulfilled via the dpSet functionality directly or indirectly) or when the timeout expires.

Set and wait for a value

main()
{
  dyn_anytype returnValues;
  bool bExpired = 0;
  int iTimeOut = 10;
 
  // Datapoint element for which a value is set
  dyn_string dpNamesSet = makeDynString("ExampleDP_Arg1.:_original.._value");
 
  // Value to set
  dyn_anytype dpValuesSet = makeDynFloat(123);
 
  // Target values for dpNamesWait
  dyn_anytype conditions = makeDynFloat(123);
 
  // DP elements to wait for values
  dyn_string dpNamesWait = makeDynString("ExampleDP_Arg2.:_online.._value");
 
  // DP elements returned when conditions for dpNamesWait are fulfilled
  dyn_string dpNamesReturn = makeDynString("ExampleDP_Arg2.:_online.._value");
 
  // Helper function to simulate a value changes when dpNamesSet are written
  DebugTN("call dpConnect");
  dpConnect("work", false, "ExampleDP_Arg1.");
 
  // Call function to write values and to wait for conditions
  DebugTN("dpSetAndWaitForValue call with timeout " + iTimeOut + " seconds");
  dpSetAndWaitForValue(dpNamesSet, dpValuesSet, dpNamesWait, conditions, dpNamesReturn, returnValues, iTimeOut, bExpired);
 
  // Check the result
  if (bExpired)
    DebugTN("Timeout of " + iTimeOut + " seconds expired - no returnValues");
  else
    DebugTN("Conditions are met - returnValues received", returnValues);
}
 
 
// Work function to simulate a value changes for dpNamesWait
void work(string dp, float value)
{
  DebugTN("Entering work function - wait 5 seconds");
  delay(5);
  DebugTN("Work function, dpSet:ExampleDP_Arg2. = " + value);
  dpSet("ExampleDP_Arg2.", value);
}

Assignment

Datapoint function, waiting Control function

Availability

CTRL