HP (Hewlett-Packard) E1432A Graphics Tablet User Manual


 
HP E1432A Interrupt Behavior
Interrupt Setup
For an example of interrupt handling see the program event.c in the
examples directory.
The HP E1432A VXI module can be programmed to interrupt a host
computer using the VME interrupt lines. VME provides seven such lines.
Using hpe1432_setInterruptPriority, you can set up the HP E1432A module
to use any one of them.
The HP 1432A can interrupt the host computer in response to different
events. Using hpe1432_setInterruptMask you can specify a mask of events
on which to interrupt. This mask is created by OR-ing together the various
conditions for an interrupt. The following table shows the conditions that
can cause an interrupt:
Interrupt Mask Bit Definitions
Define (in e1432.h) Description
HPE1432_IRQ_BLOCK_READY Scan of data ready in FIFO
HPE1432_IRQ_MEAS_ERROR FIFO overflow
HPE1432_IRQ_MEAS_STATE_CHANGE Measurement state machine changed state
HPE1432_IRQ_MEAS_WARNING Measurement warning
HPE1432_IRQ_OVERLOAD_CHANGE Overload status changed
HPE1432_IRQ_SRC_STATUS Source channel interrupt
HPE1432_IRQ_TACHS_AVAIL Raw tach times ready for transfer to other
modules
HPE1432_IRQ_TRIGGER Trigger ready for transfer to other modules
HP E1432A Interrupt Handling
To make the HP E1432A module do the interrupt, both a mask and a VME
Interrupt line must be specified, by calling hpe1432_setInterruptMask and
hpe1432_setInterruptPriority respectively. Once the mask and line have
been set, and an interrupt occurs, the cause of the interrupt can be
obtained by reading the HPE1432_IRQ_STATUS_REG register (using
hpe1432_getInterruptReason). The bit positions of the interrupt mask and
status registers match so the defines can be used to set and check IRQ bits.
HP E1432A User's Guide
Using the HP E1432A
3-29