= Description =
The [source:/Documentation/ReferenceDesigns/InterruptRef_xps_8_2 interrupt reference design] serves as an example of the proper way to handle multiple interrupts with a PowerPC. The base system is configured as shown by the figure on the right.

[[Image(interrupt_system_diagram.jpg, align=right, 300)]]

When executed, the code will periodically start a timer. By default, this timer will expire every 6 seconds. Before the timer expires, the user can depress push buttons and see confirmation of those interrupt events on a terminal connected to the board via the RS232 serial port. Upon the expiration of the timer, the [source:/Documentation/ReferenceDesigns/InterruptRef_xps_8_2/src/interruptTester.c@485#L85 timer_a_int_handler] ISR is called by the interrupt controller driver. In this ISR, the program will block for three seconds. This effectively simulates a long operation. During this time, users will not be able to trigger interrupts with push buttons. When the ISR returns, push buttons become operation again. Pressing the left button will disable the periodic timer at the interrupt controller level (i.e. the timer itself is still generating interrupt signals). Pressing the right button will re-enable the interrupts, returning the system to its normal state.

Note: Further detail regarding the interrupt system can be found in [http://direct.xilinx.com/bvdocs/appnotes/xapp778.pdf XAPP778]

= Code =

Latest Revision: [source:/Documentation/ReferenceDesigns/InterruptRef_xps_8_2/src/interruptTester.c@L interruptTester.c]