TTP-245 / TTP-343
1. FUNDAMENTAL OF THE SYSTEM ........................................................................ 1
1.1. Overview .................................................................................................................. 1
1.1.1. Front View ..................................................................................................... 1
1.1.2. Rear View ...................................................................................................... 2
1.2. Specification ............................................................................................................. 2
1.2.1. Printer ............................................................................................................ 2
1.2.2. LED ............................................................................................................... 4
1.2.3. Button ............................................................................................................ 4
1.3. Supply Specification ................................................................................................. 7
1.3.1. Paper .............................................................................................................. 7
1.3.2. Ribbon ........................................................................................................... 7
2. ELECTRONICS ........................................................................................................ 8
2.1. Circuit Description .................................................................................................... 8
2.2. MCU Circuit and MCU PIN Description..................................................................10
2.2.1. MCU PIN Description: .................................................................................. 11
2.3. Reset Circuit ............................................................................................................16
2.4. Memory Circuit .......................................................................................................17
2.5. Decoder Circuit ........................................................................................................18
2.6. Memory Map ...........................................................................................................19
2.7. Print Head Circuit ....................................................................................................21
2.8. Stepping Motor Drive / Protection Circuit ................................................................22
2.9. Power Circuit ...........................................................................................................24
2.10. Parallel Interface Circuit ........................................................................................25
2.11. Serial Interface Circuit ...........................................................................................27
2.12. USB Circuit ...........................................................................................................28
2.12.1. USB PIN Function ......................................................................................29
2.13. Sensor Circuit ........................................................................................................31
2.13.1. Gap and Black Mark Sensor ........................................................................31
2.13.2. Head Open Micro Switch ............................................................................32
2.13.3. Peel-off Sensor ............................................................................................33
2.13.4. Ribbon Sensor .............................................................................................34
2.14. Cutter Drive / Protection Circuit .............................................................................35
2.15. DC Motor Driver / Encoder Circuit ........................................................................36
2.16. Summary of PCB connectors .................................................................................37
3. REPLACE IMPORTANT PARTS ........................................................................... 40
3.1. Replacing Top Cover................................................................................................40
3.2. Replacing Top Inner Cover ......................................................................................42
3.3. Replacing Lower Cover ...........................................................................................44
3.4. Replacing Main Board .............................................................................................45