Siemens SIMATIC RF1000 Series, Руководство по эксплуатации

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Programming
6.2 Programming via USB/RS232 interface (using DLL functions)
SIMATIC RF1000
34
Operating Instructions, 02/2020, C79000-G8976-C432-07
6.2.1.11 vhl_get_snr
The function returns the serial number of the currently selected card. If the function
"vhl_select" could not be executed earlier or the card is no longer in the antenna field, the
value "CARD_NOT_SELECTED_ERR" (status code "0x0102") is returned. In this case, an
undefined serial number is returned. Note that the least significant byte of the serial number
is output first. For RF200/RF300 readers, the most significant byte is usually output first.
Function call
int
vhl_get_snr(
int Handle,
byte * Snr,
byte * Length,
int * Status
);
Table 6- 13 Description of the parameters
Parameter Description
vhl_get_snr This function call returns the serial number of the currently selected card.
Handle The session key returned by the "brp_open_usb_session" or
"brp_open_serial_session" function.
Snr Serial number of the card (LSB first)
Length Length of the serial number in bytes
Status
• OK
•
CARD_NOT_SELECTED_ERR
You will find more information on the reader status in the section "Status
codes (Page 55)".
Return value
•
BRP_OK
• CARD_NOT_SELECTED_ERR
You will find more information on return values in the section "Return val-
ues (Page 40)".