Star Micronics TUP400 Series, Technical Manual

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CHAPTER 2
THEORY OF OPERATION
This chapter describes the operating principles of the circuitry and printer mechanism.
1. Block Diagram ................................................................................................... 16
2. Main Logic Board .............................................................................................. 18
2-1. Data I/O Circuitry .................................................................................................. 18
2-1-2.RS-422A Interface ............................................................................................ 19
2-1-3. Parallel Interface .......................................................................................... 20
2-2. Editing and Printing ............................................................................................. 21
2-2-1. Editing .......................................................................................................... 21
2-2-2. Thermal Head ............................................................................................... 21
2-2-3. Head Current Control .................................................................................. 22
2-3. Feed-Motor Drive Circuit ...................................................................................... 23
2-4. Power-On Reset Circuit ....................................................................................... 24
2-5. +5V Line Voltage Detector Circuit ....................................................................... 25
3. Printer Mechanism ............................................................................................ 26
3-1. Thermal Head ........................................................................................................ 26
3-2. Paper-Feed Mechanism ....................................................................................... 26
3-3. Sensor ................................................................................................................... 27
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