Brp_Open_Usb_Session - Siemens SIMATIC RF1000 Operating Instructions Manual

6.2.1.1

brp_open_usb_session

The function opens a connection to the reader via the USB interface and returns a session
key that is required for all functions and continued communication via this connection. If the
connection was successfully established, the value "BRP_OK" is returned.
Note that all the following functions, when operating via the USB interface, can only be
performed once a connection to the reader has been established with the
"brp_open_usb_session" function. If this is not the case, an error is signaled back.
Note
Parallel operation not possible
Note that with the application, a connection can only be established to one reader at any one
time. For this reason "brp_open_usb_session" may only be called once and before it can be
called again must first be closed by the function "brp_close_session".
After a "brp_open_usb_session", the parameter "Handle" must always be = "0". If the
parameter ≠ "0", there is either an error or the function "brp_open__usb_session" was called
several times in succession.
Function call
int
brp_open_usb_session(
int * Handle,
DWORD ProductID
);
Table 6- 1
Parameter
brp_open_usb_session
Return value
SIMATIC RF1000
Operating Instructions, 02/2020, C79000-G8976-C432-07
6.2 Programming via USB/RS232 interface (using DLL functions)
Description of the parameters
Description
This function call opens a connection to the reader via the USB interface.
Handle Session key initialized by this function. The session key is valid as soon as
"BRP_OK" is returned.
ProductID 0x00
BRP_OK
•
BRP_ERR_BUSY
•
BRP_ERR_GENERAL_IO
•
BRP_ERR_BUFFER_OVERFLOW
•
BRP_ERR_NO_MORE_HANDLES
•
BRP_ERR_INSUFFICIENT_MEM
•
You will find more information on return values in the section "Return val-
ues (Page 40)".
Programming
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