* Small ZPU now supports interrupts

	* added simulation example demonstrating interrupts

1 files changed, 6 insertions, 1 deletions

diff --git a/zpu/hdl/zpu4/test/interrupt/int.c b/zpu/hdl/zpu4/test/interrupt/int.c
index 1b6ec01..6ab28f7 100644
--- a/zpu/hdl/zpu4/test/interrupt/int.c
+++ b/zpu/hdl/zpu4/test/interrupt/int.c
@@ -4,11 +4,15 @@
 #include <stdio.h>

 

 

-int counter;

+volatile int counter;

 

 /* Example of single, fixed interval non-maskable, nested interrupt. The interrupt signal is

  * held high for enough cycles to guarantee that it will be noticed, i.e. longer than

  * any io access + 4 cycles roughly.

+ * 

+ * Any non-trivial interrupt controller would have support for

+ * acknowledging interrupts(i.e. keep interrupts asserted until

+ * software acknowledges them via memory mapped IO).

  */

 void  _zpu_interrupt(void)

 {

@@ -29,6 +33,7 @@ int main(int argc, char **argv)
 		} else

 		{

 			puts("Got interrupt\n");

+			t=counter;

 		}

 	}