diff --git a/python/server.py b/python/server.py
old mode 100644
new mode 100755
index d23961e..93a4c30
--- a/python/server.py
+++ b/python/server.py
@@ -8,8 +8,8 @@ with serial.Serial('/dev/ttyACM0') as ser:
             for j in range(30): # LED
                 for k in range(3): # colour
                     for l in range(2):
-                        ser.write('f' if (i==j and k==1) else '0')
-                    ser.write('n')
-                ser.write('l')
-            ser.write('q')
+                        ser.write(b'f' if (i==j and k==1) else b'0')
+                    ser.write(b'n')
+                ser.write(b'l')
+            ser.write(b'q')