(2)Physical specifications
Table 4.1 SCSI physical specifications
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| Driver/Receiver | Single>ended | ||||||
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| Connector | 50 Contact Shielded Low Density | ||||||
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| Cable | Max. cable length | 6 m | |||||
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| Characteristic | 132 ] |
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| impedance |
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| Cable type | 25 signal twisted pair | |||
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| Stub wire | e 0. 1 mm (from main cable in scanner to internal | |||
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| wiring) | |||
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| Signal | Terminator | See the figure under (3). | |||||
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| Driver/receiver | Open collector or three> state driver | ||||
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| Output | Low level (true) = 0. 0 to 0. 5 VDC | |||
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| characteristics | High level (false) = 2. 5 to 5. 25 VDC | |||
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| Output current = 48 mA (corresponding output | |||
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| voltage e 0. 5 V) | |||
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| Input | Low level (true) = 0. 0 to 0. 8 VDC | |||
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| characteristics | 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 | See (4). | ||||||
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| for signal lines |
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(3) | Termination |
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| +5 V | |||
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220 ]
330 ]
4 $ 4