2 Visual Components Manuals

accordingly in the cyclic program.
4.10.7.1.3.2 3.2 ANSI C
4.10.7.1.3.2.1 Source code
#include
#include #include "visapi.h" _LOCAL UDINT VC_HANDLE; _LOCAL UINT
status; _LOCAL USINT step; _LOCAL USINT erase; _LOCAL USINT mtxKeys[48]; _LOCAL UDINT mtxSize;
_INIT void SetupKeyMatrix(void) { step = 0; erase = 1; } _CYCLIC void RunKeyMatrix(void) { int i; /*
get handle for project "vga1" */ if (step == 0) { VC_HANDLE = VA_Setup(1, "vga1"); if (VC_HANDLE)
step = 1; } /* try to get the key matrix */ if (step == 1) { status = VA_GetKeyMatrix(1, VC_HANDLE,
(UDINT) &mtxKeys[0], sizeof(mtxKeys) / sizeof(mtxKeys[0]), (UDINT) &mtxSize); if (status) { /* cannot
read the matrix */ erase = 1; /* handle project overload, handle becomes invalid */ if (status ==
100) step = 0; } } if (erase == 1) { /* reset all key information to unpressed on error */ for (i =
0; i < (sizeof(mtxKeys) /sizeof(mtxKeys[0])); i++) { mtxKeys[i] = 0; } erase = 0; } /* your key
handling code goes here */ }
4.10.7.1.3.3 3.3 Example Description
In the Init subprogram, the 'init' and 'erase' variables are both preset so that a connection is established first with
the respective project and the key matrix is started at 0. In this way, no key strokes can remain in the matrix if
the visualization project has not yet been started.
In the cyclic program, a connection is established with the current Visual Components project using the
VA_Setup function. This is valid until a hardware is restarted or the visualization is overloaded.
If successful, the key matrix is read with VA_GetKeyMatrix in the next code section. The size of the connected
key matrix is specified here. The actual number of keys which were copied is returned in the mtxSize parameter.
More keys than actually exist on the panel can also be requested. When touch keys are used, the number of
keys changes depending on the currently displayed picture. The user should ignore keys which do not exist in
the matrix or delete them. This is not included in the examples.
If the error code determines that the handle has become invalid in the project, a new handle is requested and
the matrix is deleted.
The last part of the cyclic program deletes the key matrix at the beginning and if an error occurs.
4.10.7.1.4 4. Adding the Application Logic
The key matrix is ready to be used by the application when the application logic is added. The corresponding
links can be placed in the the cyclic program right after the example code.
4.10.7.2 Key Matrix from Visual Components Version 2.0
For compatibility reasons, the key matrix from Visual Components Version 2.0 is still supported. However, using
the new key matrix function is recommended. Future versions of Visual Components may not support the old
key matrix.
In order to replace the old key matrix with the new one, the old one must first be deactivated using the Visual
Components global options. The new function is then used to acquire the new key matrix.
4.11 Alarm System
Introduction to Visual Components 2.3
Alarms are used to record certain conditions and occurrences in a machine. These can include passing a
threshold limit, an absence of a resource, unauthorized use of a component, or any other machine specific
situation.
Visual Components provides an integrated alarm system for managing and visualizing these alarms. The alarm
396 4.10.7.1 Using the Key Matrix