TM
CHAP. 5 MAIN …
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| This signal provides the information of d7 the eighth | |
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| DATA 7 | I | bit (MSB) of parallel data. The signal is at HIGH | ||
| level for a logical 1 and at a LOW level for a logical | |||||
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| 0. |
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| ACK | O | A 9 microsecond LOW pulse to acknowledge receipt | ||
| of data. | |||||
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| When this signal goes LOW, the printer is ready to | |
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| accept data. When the printer is in one of the | |
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| BUSY | O | conditions below, HIGH is set: | ||
| 1. | Data being entered | ||||
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| 2. | Off line |
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| 3. | Error condition |
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| PAPER END | O | This signal is normally LOW. It will go HIGH if the | ||
| printer runs out of paper. | |||||
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| SELECTED | O | This signal is HIGH when the printer is | ||
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| N/C |
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| This signal is normally HIGH. This signal goes LOW | |
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| ERROR | O | to signal that the printer cannot print due to an error | ||
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| condition | |
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| N/C |
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| When this signal goes LOW, the printer is selected to | |
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| SLCTIN | I | |||
| work. | |||||
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| GND |
| Ground | ||
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| GND |
| Ground | ||
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| GND |
| Ground | ||
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| GND |
| Ground | ||
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| GND |
| Ground | ||
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| GND |
| Ground | ||
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24 |
| GND |
| Ground | ||
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25 |
| GND |
| Ground | ||
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