TTP-248M Bar Code Printer
Service Manual
U19 is used for industrial
3.13 Parallel Port Circuit
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| PR8 10 K PR7 10 K | PR6 | 10 K | PR5 |
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| R17 |
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| 10 K |
JP4 | 38 |
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| 37 | 10 K |
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19 | 1 | /Write |
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| PR22 |
20 | 2 | D0 |
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21 | 3 | D1 |
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22 | 4 | D2 |
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23 | 5 | D3 |
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| PR23 |
24 | 6 | D4 |
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25 | 7 | D5 |
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26 | 8 | D6 |
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27 | 9 | D7 |
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| PR24 |
28 | 10 | In tr |
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29 | 11 | /Wait |
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30 | 12 | PE |
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31 | 13 | SELECT |
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| PR25 |
32 | 14 | /DStrb |
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33 | 15 | /AStrb |
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34 | 16 | ERROR |
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35 | 17 | /In it |
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| R56 |
36 | 18 |
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| VDD |
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| R19 |
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CENTRONIC |
| 10 K |
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GND DIGITAL GND |
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PC1 | 22 0p PC2 | 22 0p PC3 | 22 0p PC4 | 22 0p |
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| C5 |
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| 22 0p |
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| U6A |
| 74 HCT1 4 | /Write/Writ e | |
10 0 |
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| 1 |
| 2 |
| U2/9 8 |
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| D0 |
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| U2/1 00 | |
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| D1 |
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| U2/1 01 | |
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| D2 |
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| U2/1 02 | |
10 0 |
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| D3 |
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| U2/1 03 | ||
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| D4 |
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| U2/1 04 | |
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| D5 |
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| U2/1 05 | |
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| D6 |
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| U2/1 06 | |
10 0 |
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| D7 |
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| U6F |
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| U2/1 07 | ||
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| 12 | 13 |
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| U2/1 10 | |||
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| /Wait |
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| 74 HCT1 4 |
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| U2/1 11 | |
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| 11 |
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| 10 |
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10 0 |
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| U6E | 74 HCT1 4 |
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| /DStrb | U2/1 12 | |
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| /AStrb | ||
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| U2/1 13 | ||
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10 0 |
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| /In it |
| U2/1 15 |
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| 4 |
| 3 |
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| PE | |||
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| R18 |
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| 6 U6C | U6B5 | 74 HCT1 4 |
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| 10 K |
| SELECT |
| SELECT | ||||
VDD |
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| U6D |
| 74 HCT1 4 |
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| 8 | 9 |
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| ERROR |
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| ERROR | |||
PR1 | 10 K | PR2 | 10 K PR3 | 10 K PR4 | 10 K |
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| 74 HCT1 4 |
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Fig. 3.16 Parallel Port Circuit
Censorings port is SPP mode and
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