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Inserting these values into the equations defined above allows you to determine the values for SETUP, STROBE, HOLD, and TA. For a read:
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| tEM_A ) tACC(m) ) tSU ) tEM_D |
| (0.27 ) 12 ) 5 ) 0.45) |
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R_SETUP ) R_STROBE w |
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tcyc |
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| tRC(m) |
| 12 |
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R_SETUP ) R_STROBE ) R_HOLD w |
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| * 3 | w 10* | 3 w * 1.8 | ||||||||||||||
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R_HOLD w | tH * tEM_D * tOH(m) * tEM_A | * 1 | (0 * 0.45 * 3 * 0.27) | 1 w * 1.37 | ||||||||||||||||
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| tEM_CS ) TCOD(m) ) tEM_D |
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| (0.36 ) 7 ) 0.45) |
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TA w |
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Therefore if R_SETUP = 0, then R_STROBE = 0, R_HOLD = 0, and TA = 0.
For a write:
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| tWP(m) | 8 | * 1 w * 0.2 |
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W_STROBE w |
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tcyc | 10 |
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W_SETUP ) W_STROBE w max | tEM_A ) tAW(m) * tEM_WE | , | tEM_D ) tDS (m) * tEM_WE | * 1 | ||||
| tcyc | tcyc |
wmax(0.36 ) 0 * 0.27) , (0.36 ) 0 * 0.45)* 1 w * 0.92
1010
W_HOLD w max | tEM_WE ) tWR(m) * tEM_A | , | tEM_WE ) tDH(m) * tEM_D | * 1 | |
tcyc |
| tcyc |
wmax(0.27 ) 9 * 0.36) , (0.45 ) 7 * 0.36)* 1 w * 0.1
1010
W_SETUP ) W_STROBE ) W_HOLD w tWC(m) * 3 w 12* 3 w * 1.8
tcyc10
Therefore, W_SETUP = 0, W_STROBE = 0, and W_HOLD = 0.
38 | Asynchronous External Memory Interface (EMIF) | SPRUEQ7C |
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