diff options
| author | Bert Lange <b.lange@hzdr.de> | 2015-04-15 13:36:55 +0200 |
|---|---|---|
| committer | Bert Lange <b.lange@hzdr.de> | 2015-04-15 13:36:55 +0200 |
| commit | a1c964908b51599bf624bd2d253419c7e629f195 (patch) | |
| tree | 06125d59e83b7dde82d1bb57bc0e09ca83451b98 /zpu/hdl/zpu4/test/interrupt/int.c | |
| parent | bbfe29a15f11548eb7c9fa71dcb4d2d18c164a53 (diff) | |
| parent | 8679e4f91dcae05aef40f96629f33f0f4161f14a (diff) | |
| download | zpu-a1c964908b51599bf624bd2d253419c7e629f195.zip zpu-a1c964908b51599bf624bd2d253419c7e629f195.tar.gz | |
Merge branch 'master' of https://github.com/zylin/zpu
Diffstat (limited to 'zpu/hdl/zpu4/test/interrupt/int.c')
| -rw-r--r-- | zpu/hdl/zpu4/test/interrupt/int.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/zpu/hdl/zpu4/test/interrupt/int.c b/zpu/hdl/zpu4/test/interrupt/int.c new file mode 100644 index 0000000..6ab28f7 --- /dev/null +++ b/zpu/hdl/zpu4/test/interrupt/int.c @@ -0,0 +1,40 @@ +/*
+ * Shows usage of interrupts. Goes along with zpu_core_small_wip.vhd.
+ */
+#include <stdio.h>
+
+
+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)
+{
+ /* interrupts are enabled so we need to finish up quickly,
+ * lest we will get infinite recursion!*/
+ counter++;
+}
+
+int main(int argc, char **argv)
+{
+ int t;
+ t=counter;
+ for (;;)
+ {
+ if (t==counter)
+ {
+ puts("No interrupt\n");
+ } else
+ {
+ puts("Got interrupt\n");
+ t=counter;
+ }
+ }
+
+}
|
