Interface
5.5.6 Series termination required for Ultra DMA
Series termination resistors are required at both the host and the device for operation in any of the Ultra DMA Modes. The following table describes recommended values for series termination at the host and the device.
Table 5.17 Recommended series termination for Ultra DMA
Signal | Host Termination | Device Termination |
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33 Ω | 82 Ω | |
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33 Ω | 82 Ω | |
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33 Ω | 82 Ω | |
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DA0, DA1, DA2 | 33 Ω | 82 Ω |
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DMACK- | 33 Ω | 82 Ω |
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DD15 through DD0 | 33 Ω | 120 Ω (100 MHz) |
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DMARQ | 82 Ω | 33 Ω |
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INTRQ | 82 Ω | 33 Ω |
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82 Ω | 22 Ω | |
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Note: Only those signals requiring termination are listed in this table. If a signal is not listed, series termination is not required for operation in an Ultra DMA Mode. For signals also requiring a
IORDY | DMARQ |
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|
Figure 5.9 Ultra DMA termination with pull-up or pull-down
Configuration of cable
For the configuration of the cable (common use of primary port and secondary port), DMACK signal should not be used in common. It is not recommended to use