Sensor - Star Micronics TUP400 Series Technical Manual

3-3. Sensor

(1) Paper-Out Sensor
The paper-out sensor is located at the paper entry slit. The detector consists of a reflective photosensor. The
photosensor's phototransistor remains ON while paper is present. It goes OFF when paper runs out, generating
output of a paper-out signal.
(2) Black-Mark Sensor
This detector senses black marks indicating print start positions. The detector is useful only with specially marked
paper. Like the paper-out detector, the black-mark detector consists of a reflective photosensor. The photosensor's
phototransistor goes OFF when a black mark appears.
GND
+5V
Detection Signal
Fig. 2-15 Paper-Out Detector
(3) Paper Near-end Sensor
The Paper Near-end Sensor detects the amount of paper remaining on the roll. When the roll paper no longer exists
at the set position, the reflective photosensor turns OFF and outputs a no paper signal.
R
R
(Reflective Photosensor)
GND
+5V
Detection Signal
Fig. 2-17 Paper Near-end Sensor
Paper
GND
+5V
Detection Signal
Fig. 2-16 Black-Mark Detector
R
R
(Reflective Photosensor)
– 27 –
R
R
(Reflective Photosensor)
Paper
Paper
Black Mark