2 fc8 ag_unlock – Siemens Simantic Net NCM for Industrial Ethernet S7 User Manual

Page 171

Advertising
background image

Programming FCs (Functions) and FBs for S7 Ethernet CPs

171

SIMATIC NET NCM S7 for Industrial Ethernet
C79000-G8976-C129–06

5.4.2

FC8 AG_UNLOCK

Meaning of the Block

Using the AG_UNLOCK function, the external access to system areas on the S7
CPU with FETCH or WRITE on the connection specified by the ID parameter is
released.

The next external FETCH/WRITE job to arrive for the CP can then be processed.

The AG_UNLOCK follows an access lock with AG_LOCK.

Call

Representation of the AG_UNLOCK Function

LADDR

AG_UNLOCK

ID

STATUS

Example in STL representation

STL

Explanation

call fc 8
ID

:=

DB 100.DBW 2

LADDR

:=

W#16#0100

STATUS

:=

DB 100.DBW 4

//Block call
//Connection ID acc. to configuration

//=LADDR 256 dec. in hardware configuration
//Status code

How the Block Works

To release the connection again, the LOCK request bit must be reset by the FC
again. The FC also shows the current status using error messages.

Explanation of the Formal Parameters

The following table explains all the formal parameters for the AG_UNLOCK
function:

Advertising