diff --git a/demo/can.cpp b/demo/can.cpp
index 37ca739..1d20b24 100644
--- a/demo/can.cpp
+++ b/demo/can.cpp
@@ -38,11 +38,13 @@ can_frame can_read(void) {
 }
 
 void can_isr(void) {
+	static uint32_t count = 0;
 	can_ev_pending_frame_write(1);				// Should use `can_ev_pending_read()` and check which interrupt, but there is only 1
 	leds_out_write(leds_out_read() ^ 0xFF0000); // Toggle Red LED
+	count++;
 	can_frame frame = can_read();
-	printf("\033[F\033[F\33[2K\nCAN frame received, ID: 0x%03X, data: 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X\n",
-		   frame.id, frame.data[0], frame.data[1], frame.data[2], frame.data[3], frame.data[4], frame.data[5],
+	printf("\033[F\033[F\33[2K\nCAN frame % 5d received, ID: 0x%03X, data: 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X 0x%02X\n",
+		   count, frame.id, frame.data[0], frame.data[1], frame.data[2], frame.data[3], frame.data[4], frame.data[5],
 		   frame.data[6], frame.data[7]); // Print CAN frame to UART
 	can_ev_enable_frame_write(1);		  // Re-enable event handler, same as in `can_init()`
 	printf("\e[92;1mStackSynth\e[0m> ");  // Print prompt to UART
diff --git a/demo/main.cpp b/demo/main.cpp
index 749f116..2774480 100644
--- a/demo/main.cpp
+++ b/demo/main.cpp
@@ -23,6 +23,7 @@ char *readstr(bool print) {
 	static unsigned int ptr = 0;
 
 	if (print) {
+		s[ptr] = 0x00;
 		fputs(s, stdout);
 	} else if (readchar_nonblock()) {
 		c[0] = getchar();