Sercos3_IDNRead4 (FB)

FUNCTION_BLOCK Sercos3_IDNRead4

This function block could be used to read Sercos III slave parameter. In contrast to Sercos3_IDNRead only parameters not longer than 4 Bytes will be supported. The parameter to be read is specified by the IDN as used in the object dictionary.

InOut:

Scope	Name	Type	Initial	Comment
Input	xExecute	BOOL		On a rising edge at this input the reading of the slave parameter will be started. In order to get the internal channel deallocated, the instance must be called at least once by “xExecute:= FALSE”.
	xAbort	BOOL	FALSE	If this parameter is TRUE, the current read process will be aborted.
	usiCom	USINT	1	Number of the Sercos III master: If only one Sercos III master is used, usiCom is ‘1’. In case of multiple masters use ‘1’ for the first, ‘2’ for the second, etc.
	uiAddress	UINT		Topological address or Sercos address, depends on the parameter xIsSercosAddress
	xIsSercosAddress	BOOL	FALSE	This input switches between topological address and Sercos address FALSE: uiAddress is the topological address TRUE: uiAddress is the Sercos address
	usiChannel	USINT	1	Reserved for future extensions. Currently not used.
	dwIDN	DWORD		IDN (Identification Number) with 4 Bytes (SI (structure instance) and SE (structure element))
	wElem	WORD		Value 1: Structure of the IDN Value 2: Name of the parameters Value 3: Data attributes Value 4: Unit Value 5: Minimal value Value 6: Maximal value Value 7: Data value
	udiTimeOut	UDINT		Here you can set a timeout in milliseconds. If the reading of the parameter has not been finished within this time, an error message will be generated.
Output	xDone	BOOL		This output is TRUE as soon as the command has been finished successfully.
	xBusy	BOOL		This output is TRUE as long as the execution of the command has not been finished.
	xError	BOOL		This output is TRUE, if an error is detected. eError will show the cause.
	eError	SERCOS3_ERROR		This output shows the cause of the detected error, which is indicated by xError. For example ‘SERCOS3_TIMEOUT’ in case of an timeout.
	udiSercosError	UDINT		Error code if the function block has not been finished successfully.
	abyData	ARRAY [1..4] OF BYTE		This is an array of 4 Bytes to which the read parameter data will be copied. If 1 Byte have been read, this will be stored in index 1 of the array. Values of 2 resp. 4 bytes will be copied to the array according to Intel byte order.
	usiDataLength	USINT		Number of read bytes (1,2,4).