![](/images/new-backgrounds/1109578/10957845x1.webp)
Airborne Enterprise Module Databook |
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| Quatech, Inc. | |||
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| Table 13 - SPI AC Timings |
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| Symbol | Parameter | Min | Typ | Max |
| Units |
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| fMAX | Maximum Clock Frequency |
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| 8.00 |
| MHz |
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| tCS | SPI Select Low to Clock Rising Edge | 100 |
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| ns |
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| tCH | Clock High | 62.5 |
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| ns |
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| tCL | Clock Low | 62.5 |
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| ns |
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| tDA | Clock High to Data Out |
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| 60 |
| ns |
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| tDS | Clock Low to Data In Valid | 14 |
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| ns |
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| tDH | Clock Low to Data Valid Hold time | 2 |
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| ns |
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| tCSH | Clock Falling Edge to SPI Select High | 100 |
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| ns |
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| tDELAY | SPI Select High to SPI Select Low | 40 |
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| ns |
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Figure 3 - SPI Read/Write Timing
Figure 4 - SPI Clock and Select Timing
7.3SPI Protocol
A SPI message is composed of a 4 byte header followed by 0 or more bytes of data. The header data is
8/11/2009 | 23 |