Programming interface
4.1 The functions of the DLL
SIMATIC RF1060R
18
Operating Instructions, 05/2017, C79000-G8976-C432-02
4.1.9
vhl_is_selected
This function checks whether the card selected the last time the "vhl_select" function
executed is still or once again located in the antenna field. If the card is there, the status
"OK" is returned.
Note that this function always returns "CARD_NOT_SELECTED_ERR" when a card is
shown a card without the "vhl_select" function being executed first.
Function call
int
vhl_is_selected(
int Handle,
int * Status
);
Description of the parameters
Parameter
Description
vhl_is_selected
This parameter checks whether the card selected the last time the
"vhl_select" function executed is still or once again located in the antenna
field.
Handle
The session key returned by the function "brp_open_usb_session()".
Status
You will find more information on the reader status in the section "Status
Return value
•
BRP_OK
You will find more information on return values in the section "Return val-
4.1.10
Return values
The following table contains a list of the possible values that the reader can return for the
various functions.
Value Variable
Description
0x00
BRP_OK
No error has occurred
0x01
BRP_ERR_STATUS
The reader has returned a status code that is
≠
"0".
0x02
BRP_ERR_BUSY
The reader is currently processing a function.
0x03
BRP_ERR_IDLE
The reader is waiting for a function.
0x04
BRP_ERR_TIMEOUT
The response time has been exceeded.
0x05
BRP_ERR_CORRUPTED_FRAME
A bad frame was detected.
0x06
BRP_ERR_UNEXPECTED_FRAME An unexpected frame was detected.
0x07
BRP_ERR_GENERAL_IO
The underlying serial port has caused an error.
0x08
BRP_ERR_BUFFER_OVERFLOW
The reader sent more data than expected.
0x09
BRP_ERR_NO_MORE_HANDLES
There is no free session key.
