SPRS293 − OCTOBER 2005
MULTICHANNEL BUFFERED SERIAL PORT TIMING (CONTINUED)
timing requirements for FSR when GSYNC = 1 (see Figure 42)
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1 | Setup time, FSR high before CLKS high |
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| 4 |
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2 | Hold time, FSR high after CLKS high |
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| 4 |
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| CLKS |
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| 1 |
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FSR external
CLKR/X (no need to resync)
CLKR/X (needs resync)
Figure 42. FSR Timing When GSYNC = 1
timing requirements for McBSP as SPI master or slave: CLKSTP = 10b, CLKXP = 0†‡ (see Figure 43)
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| −150 |
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NO. |
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| MASTER |
| SLAVE |
| UNIT |
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| MIN MAX |
| MIN | MAX |
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4 | Setup time, DR valid before CLKX low | 12 |
| 2 − 6P |
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5 | Hold time, DR valid after CLKX low | 4 |
| 5 + 12P |
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†P = 1/CPU clock frequency in ns. For example, when running parts at 150 MHz, use P = 6.7 ns.
‡ For all SPI slave modes, CLKG is programmed as 1/2 of the CPU clock by setting CLKSM = CLKGDV = 1.
POST OFFICE BOX 1443 • HOUSTON, TEXAS 77251−1443 | 89 |