Chapter 8
Interrupt Control
©
National Instruments Corporation
8-3
DAQ-STC Technical Reference Manual
8.4 Programming Information
This section presents programming information that is specific to the ICM. For general
information about programming the DAQ-STC, see section
.
8.4.1 Programming the Interrupt Interface
This section contains detailed programming information for users who need to do bit-level
programming of the interrupt interface for specialized applications.
The DAQ-STC can be used as an interrupt management device. The DAQ-STC can generate
interrupts on up to 18 internal conditions and can propagate two externally generated
interrupts. Ten pins are provided for the interrupt interface: pins IRQ_OUT<0..7> can be used
for interrupt assertion, and pins IRQ_IN<0..1> can be used for interrupt propagation.
Interrupts on the DAQ-STC are divided into groups A and B. Details are provided in section
.
8.4.1.1
I
nterrupt Output Polarity
Use the following function to select the logic level that will indicate an interrupt condition on
the IRQ_OUT pins and to indicate whether you want the selected interrupt to be duplicated
on the IRQ_OUT<0..1> pins.
Function
MSC_IRQ_Personality
{
Interrupt_Output_Polarity = 0 (for active high) or 1 (for active low);
Interrupt_Output_On_3_Pins = 0 (disabled) or 1 (enabled);
}
8.4.1.2 Interrupt Output Select and Enable
Use the following function to select the IRQ_OUT pin that will indicate an interrupt condition
in the interrupt group and to enable interrupts for the group.
Function
MSC_IRQ_Configure
{
switch (interrupt group)
{
case A:
Interrupt_A_Output_Select = 0 through 7 (IRQ_OUT<0..7>);
Interrupt_A_Enable = 0 (disabled) or 1 (enabled);
break;
case B:
Interrupt_B_Output_Select = 0 through 7 (IRQ_OUT<0..7>);