This is a photo-interrupter-type sensor. When paper is supplied from the paper tray, or roll feed unit, the sensor light is blocked by the sensor arm, thus detecting
paper.
Spur cam sensor
This is a photo-interrupter-type sensor.
When the sensor light is shielded by the rotation of the spur motor, the printer detects that the spur unit is at the upper-limit position.
When the sensor light is unshielded by the rotation of the spur motor, the printer detects that the spur unit is at the bottom position.
The spur height is controlled by driving the spur motor with a predetermined number of pulses.
Cutter HP sensor
This is a photo-interrupter-type sensor. This sensor detects that the cutter is at the home position (left end).
Cutter right position sensor
This is a photo-interrupter-type sensor. This sensor detects that the cutter is at the right end.