Addi-Data APCI-1710 Technical Description page 72

APCI-1710
WICHTIG!
i
For Windows NT and Windows 95, 4 rings are available (ring 0
to ring 3).
- The user application program runs under ring 3. In this ring no access to
hardware is available.
- VXD and SYS drivers run under ring 0 and have hardware access.
- Ring 0 cannot access to the variable of ring 3 and therefore shall use the
Shared Memory.
- Ring 0 und ring 3 have an indicator, which identifies this Shared Memory.
Both rings have different addresses.
This function is to be called for all xPCI-1710 boards on which you want to
activate an interrupt.
At the first calling of a function (first board):
- the user interrupt routine is installed
- the interrupts are made possible.
- the user shared memory will be allocated if the following mode is
activated:
APCI1710_SYNCHRONOUS_MODE.
If you operate various xPCI-1710 boards that shall react to interrupts, you
shall call the function as many times as how many xPCI-1710 boards you
are operating.
The variable v_FunctionName is only at the first calling of importance.
From the second calling of a function on (next boards) interrupts are
enabled.
Interrupt
If an interrupt is generated, the user interrupt routine of the system is called.
If various boards are operated and shall react to interrupts, the variable
b_BoardHandle shows the identification number (handle) of the board,
which has generated the interrupt.
The user interrupt can be called as follows:
- directly from the interrupt routine of the driver (synchronous mode). The
code of the user interrupt routine runs directly under ring 0.
- or of the Interrupt Thread of the driver (synchronuous mode). An event
will be generated and the Interrupt Thread calls the user interrupt routine.
The code of the user interrupt routine runs under ring 3.
The Interrupt Thread of the driver has the highest priority (31) in the
system.
Standard software
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