diff --git a/Apple1.ino b/Apple1.ino
index 1e35f89..5faabc2 100644
--- a/Apple1.ino
+++ b/Apple1.ino
@@ -34,7 +34,7 @@ void reset() {
 		io.status("Reset failed");
 		return;
 	}
-	io.files.start();
+	io.start();
 #if defined(KRUSADER)
 	io.status("Krusader: F000R / Basic: E000R");
 #else
diff --git a/io.cpp b/io.cpp
index 745119d..4898afc 100644
--- a/io.cpp
+++ b/io.cpp
@@ -1,5 +1,4 @@
-#include <Stream.h>
-#include <stdint.h>
+#include <Arduino.h>
 #include <memory.h>
 #include <display.h>
 #include <serialio.h>
@@ -26,6 +25,28 @@ void io::reset() {
 	PIA::reset();
 }
 
+static io *i;
+
+const int TICK_FREQ = 2;
+
+bool io::start() {
+
+	i = this;
+	timer_create(TICK_FREQ, io::on_tick);
+	return files.start();
+}
+
+void IRAM_ATTR io::on_tick() {
+
+	static int tick = 0;
+	tick = ++tick % 3;
+	i->cursor(tick < 2);
+}
+
+void io::cursor(bool on) {
+	draw(on? '_': ' ', c, r);
+}
+
 void io::load() {
 	if (files.more()) {
 		_loading = true;
diff --git a/io.h b/io.h
index 619e0ec..2a8c418 100644
--- a/io.h
+++ b/io.h
@@ -5,18 +5,22 @@ class io: public Memory::Device, public Display, Keyboard, public PIA {
 public:
 	io(filer &files): Memory::Device(Memory::page_size), files(files) {}
 
-	virtual void reset();
-	virtual void down(uint8_t);
-	virtual void up(uint8_t);
+	void reset();
+	bool start();
 
-	virtual void operator=(uint8_t b) { PIA::write(_acc, b); }
-	virtual operator uint8_t() { return PIA::read(_acc); }
+	static void on_tick();
 
-	virtual void checkpoint(Stream &);
-	virtual void restore(Stream &);
+	void down(uint8_t);
+	void up(uint8_t);
 
-	virtual void write_portb(uint8_t);
-	virtual uint8_t read_cra();
+	void operator=(uint8_t b) { PIA::write(_acc, b); }
+	operator uint8_t() { return PIA::read(_acc); }
+
+	void checkpoint(Stream &);
+	void restore(Stream &);
+
+	void write_portb(uint8_t);
+	uint8_t read_cra();
 
 	void load();
 	filer &files;
@@ -25,6 +29,7 @@ public:
 	static const uint8_t COLS = 40;
 
 private:
+	void cursor(bool on);
 	void display(uint8_t);
 	void draw(char, int, int);
 	void enter(uint8_t);