A.1 Physical Specifications
(2)Physical specifications
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| Table A.1 SCSI physical specifications | ||||
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Driver/Receiver |
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Connector |
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| 50 Contact Shielded Low Density | |||||
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Cable |
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| Max. cable length |
| 6 m | |||
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| Characteristic |
| 132 Ω | |||
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| impedance |
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| Cable type |
| 25 signal twisted pair | |||
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| Stub wire |
| ≤ 0.1 mm (from main cable in scanner to internal wiring) | |||
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Signal |
| Terminator |
| See the figure under (3). | ||||
level |
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| Driver/receiver |
| Open collector or | ||||
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| Output characteristics |
| Low level (true) = 0.0 to 0.5 VDC | |||
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| High level (false) = 2.5 to 5.25 VDC | |||
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| Output current = 48 mA (corresponding output voltage ≤ 0.5 V) | |||
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| Input characteristics |
| Low level (true) = 0.0 to 0.8 VDC | |||
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| High level (false) = 2.0 to 5.25 VDC | |||
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| Input load = | |||
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| Input hysteresis = 0.2 VDC min. | |||
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Connector pin assignments for |
| See (4). | ||||||
signal lines |
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(3) | Termination |
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| +5 V | |||
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220 Ω¶
- signal
330 Ω
Appendix