Scanlab RTC6 PCIe Board - Select_Rtc

RTC6 boards
Doc. Rev. 1.0.21 en-US
10 RTC6 Commands
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Ctrl Command select_rtc
Function Defines, in a multi-board system, the active RTC6 board for a user program.
See Chapter 6.6 ”Using Several RTC6 PCIe Boards in One PC”, page 123.
Call NoOfSelectedCard = select_rtc( CardNo )
Parameters CardNo RTC6 DLL-internal number of the RTC6 board.
As an unsigned 32-bit value.
Result The returned value is:
• CardNo if access rights exist for the specified board or if the specified board is not
allocated to another user program (in this latter case, access rights are acquired
through select_rtc – as by acquire_rtc, see below).
• The number of the active board if CardNo exceeds the number of RTC6 boards found
during initialization, no RTC6 Ethernet Board is entered there or if CardNo = 0.
• 0 otherwise (particularly when the specified board is reserved by another user program
or if a version compatibility error is detected and activation of the board therefore
cannot succeed) (get_last_error return code RTC6_ACCESS_DENIED and possibly
RTC6_VERSION_MISMATCH ).
As an unsigned 32-bit value.
Comments • Activation of a board for a user program already occurs when the RTC6 DLL for this
user program is initialized (see init_rtc6_dll). The select_rtc command offers the
possibility of changing the active board at any time. All user program commands
subsequent to select_rtc (except for multi-board commands) are forwarded to the
corresponding active board.
• If the specified board is reserved for another user program, select_rtc has no effect
(return value 0, get_last_error return code RTC6_ACCESS_DENIED ).
• If the specified board has no access rights granted and is not acquired by another
user program, an attempt is made to acquired it (as by acquire_rtc).
If a board is acquired (as by acquire_rtc), a version compatibility check is performed.
If a version error is detected, then access to the board is denied and select_rtc has no
effect (return code 0, get_last_error return code
RTC6_ACCESS_DENIED | RTC6_VERSION_MISMATCH ).
• If the specified board is already the active board for this user program, select_rtc has
no effect (return value: CardNo ).
• The select_rtc command also has no effect if CardNo exceeds the number of
RTC6 boards found during initialization (see rtc6_count_cards), no RTC6 Ethernet
Board is entered there or if CardNo = 0 (real boards begin at 1). The return value is then
the number of the active board (see above). Therefore, select_rtc( 0 ) can be used to
determine the number of the active board at any time.
• The select_rtc command is available even without explicit access rights to a particular
RTC6 board.
• select_r
tc is not available as a multi-board command.