6.2.4.Timing of Host Interface (Ultra DMA )
Figure 15 shows the Host Interface Ultra DMA word Timings
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| tMLI |
DMARQ | tUI |
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DMACK- |
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| tACK | tFS | t2CYC | tRP |
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STOP |
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| tCYC | tCYC |
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| tENV |
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| tACK | ||
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| tLI | ||
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DMARDY |
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| t2CYC |
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| tZAD |
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| tRFS |
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| tZIORDY |
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STROBE |
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| tDVS tDVH tDVS | tDVH | tDVS tDVH | tDVS tDVH | |
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DD (15:0) |
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| CRC |
Sender |
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| tZAD |
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tZIORDY
STROBE |
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tDS t D H tDS | tDH tDS | tDS tDH |
tDH | ||
DD (15:0) |
| CRC |
Recipient |
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In all timing diagrams, the low line indicator negated, and the upper line indicators asserted.
| Ultra DMA Mode 2 | Min time (ns) | Max time (ns) |
| Timing parameters min (ns) max (ns) | ||
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| Typical Sustained Average Cycle time | 120 |
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t2CYC |
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Two cycle time (from rising edge to next rising edge of | 117 |
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| from falling edge to next falling edge of STROBE) |
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tCYC | Cycle time allowing | 55 |
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tDVS | Data valid Setup time | 34 |
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tDVH | Data valid Hold time | 6 |
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tUI | Unlimited Interlock time | 0 |
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tACK | Setup and Hold Time for DMACK- | 20 |
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tENV | Envelope time | 20 | 70 |
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tZAD | Minimum Delay time for Driver | 0 |
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tZIORDY | Minimum time for DMACK- | 20 |
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tFS | First STROBE time | 0 | 170 |
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tRFS |
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tRP | 100 |
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tLI | Limited Interlock time | 0 | 150 |
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tMLI | Interlock with minmum | 20 |
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tDS | Data setup time (at recipient) | 7 |
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tDH | Data hold time (at recipient) | 5 |
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Figure 15 Host Interface Timing (Ultra DMA Mode 2)
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