diff --git a/demo/Makefile b/demo/Makefile
index 96da1d5..b4a494c 100644
--- a/demo/Makefile
+++ b/demo/Makefile
@@ -3,7 +3,7 @@ BUILD_DIR?=../build/gsd_orangecrab/
 include $(BUILD_DIR)/software/include/generated/variables.mak
 include $(SOC_DIRECTORY)/software/common.mak
 
-OBJECTS = audio.o can.o crt0.o donut.o led.o main.o
+OBJECTS = audio.o can.o crt0.o donut.o isr.o led.o main.o
 CFLAGS += -DWITH_CXX
 
 
diff --git a/demo/isr.cpp b/demo/isr.cpp
new file mode 100644
index 0000000..3032651
--- /dev/null
+++ b/demo/isr.cpp
@@ -0,0 +1,30 @@
+// This file is Copyright (c) 2013-2014 Sebastien Bourdeauducq <sb@m-labs.hk>
+// This file is Copyright (c) 2019 Gabriel L. Somlo <gsomlo@gmail.com>
+// This file is Copyright (c) 2020 Raptor Engineering, LLC <sales@raptorengineering.com>
+// License: BSD
+
+#include "can"
+#include <generated/csr.h>
+#include <generated/soc.h>
+#include <irq.h>
+#include <libbase/uart.h>
+#include <stdio.h>
+
+#ifdef CONFIG_CPU_HAS_INTERRUPT
+void isr(void) {
+	__attribute__((unused)) unsigned int irqs;
+
+	irqs = irq_pending() & irq_getmask();
+
+#ifdef CSR_UART_BASE
+#ifndef UART_POLLING
+	if (irqs & (1 << UART_INTERRUPT))
+		uart_isr();
+#endif
+#ifdef CAN_INTERRUPT
+	if (irqs & (1 << CAN_INTERRUPT))
+		can_isr();
+#endif
+#endif
+}
+#endif