Star Micronics TSP400 technical manual Timing Chart

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THEORY OF OPERATION

CLOCK

SI

LATCH

STROBE1

STROBE2

STROBE3

STROBE4

STROBE5

COMMON

t

24V

Fig.2-6 Timing Chart

2-2-3. Head current control

Heat buildup in the head during operation can cause print quality to degrade. To maintain uniform quality, the printer varies the energizing time (time that STROBE remains LOW) in accordance with the head temperature.

The thermal head’s surface temperature is calculated based on the resistance value of an attached thermistor. Energizing time is reduced at higher temperatures, as indicated in the figure 2-6.

STROBE1, STROBE2, STROBE3

STROBE4, STROBE5,

EnergizingTime￿

600

(tμsec)

 

500

 

400

Head

300

 

t

t

10

20

30

40

50

Thermistor Temp. (°C)

Fig. 2-7 Head Energizing Control

– 25 –

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Contents TSP400 Series Page Introduction Page Chapter Specifications and Operation Specifications and Operation OCR-B General SpecificationsInternal Configuration TSP412D External Appearance and Internal ConfigurationDIP-Switch Settings Status of printer power Baud Print-Density Adjustment Sensor Adjustment Specifications and Operation Setting Memory Switches from the Control Panel HEX Dump Test PrintPage/Line Mode Switch Exposing the Peripheral Unit Connector Changing the Interface Board Specifications and Operation Chapter Theory of Operation Theory of Operation 24V Block DiagramControl Panel Interface Main and Interface PCBs2. RS422A interface Parallel Interface PCB Main PCB Editing Editing and PrintingTiming Chart Feed-Motor Drive Circuit Motor Control by Phase 1-2 ExcitationPower-On Reset Circuit 11 Equivalence Circuit for Voltage Detecting IC +5V Line Voltage Detector CircuitPaper-Feed Mechanism Printer MechanismThermal Head 15 Paper-Out Detector Detectors19 Head-Up Detector Page Chapter Parts Replacement and Related Adjustments Parts Replacement TSP412D Upper Casing UnitControl-Panel Board Printer Mechanism Main PCB, Interface PCB Fuse Power UnitPrinthead unit Feed Motor AssemblyLabel sensor DetectorsParts Replacement Chapter Maintenance and Lubrication Maintenance and Lubrication Checks MaintenanceCleaning Lubricants LubricationApplication Method Lubrication PointsLubrication Points Maintenance and Lubrication Chapter Parts List Disassembly Drawing Printer AssemblyTSP442D Printer Assembly Parts ListScrew TAT Printer Mechanism Assembly Oiless Bushing F4X7X3 Printer MechanismRS-232C Interface Type Connector Wiring DiagramRS422A I/F Board Control Board Parallel Interface Type Main Logic Board Circuit DiagramSide a Side D Side C Main Logic Board Chip Resistor 20 K-OHM 1/10W CN8 RS232C Interface RS232C Interface Board RS422A Interface RS422A Interface Board CentronicsInterface Centronics Interface Board Control Panel Board Control Panel Board Label Sensor Board Paper-Out Detector BoardPaper-Out Detector Transmissive SensorPage Distributed by