diff --git a/software/control/microscope.py b/software/control/microscope.py
index 6ef3d627..94a27028 100644
--- a/software/control/microscope.py
+++ b/software/control/microscope.py
@@ -296,6 +296,7 @@ def turn_on_illumination(self, channel=None):
             if self.shutter_control_mode == ShutterControlMode.Software:
                 self.light_source.setLaserOnOff(self.channel_mappings_software[channel], on=True)
             elif self.shutter_control_mode == ShutterControlMode.TTL:
+                self.microcontroller.turn_on_illumination()
 
         self.is_on[channel] = True
 
@@ -305,6 +306,7 @@ def turn_off_illumination(self, channel=None):
             if self.shutter_control_mode == ShutterControlMode.Software:
                 self.light_source.setLaserOnOff(self.channel_mappings_software[channel], on=False)
             elif self.shutter_control_mode == ShutterControlMode.TTL:
+                self.microcontroller.turn_off_illumination()
 
         self.is_on[channel] = False