Texas Instruments SM320C6455-EP, Руководство по данным

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AECLKOUT
ACEx
ABE[7:0]
AEA[19:0]/ABA[1:0]
AED[63:0]
ASADS/ASRE
(B)
AAOE/ASOE
(B)
AAWE/ASWE
(B)
BE1 BE2 BE3 BE4
Q1 Q2 Q3
11
3
12
10
4
2
1
8
5
8
EA1 EA2 EA3 EA4
10
Write
Latency =
1
(B)
1
Q4
12
A The following parameters are programmable via the EMIFA Chip Select n Configuration Register (CESECn):
− Read latency (R_LTNCY): 1-, 2-, or 3-cycle read latency
− Write latency (W_LTNCY): 0-, 1-, 2-, or 3-cycle write latency
− ACEx assertion length (CE_EXT): For standard SBSRAM or ZBT SRAM interface, ACEx goes inactive after the final command has been
issued (CE_EXT = 0). For synchronous FIFO interface, ACEx is active when ASOE is active (CE_EXT = 1).
− Function of ASADS/ASRE (R_ENABLE): For standard SBSRAM or ZBT SRAM interface, ASADS/ASRE acts as ASADS with deselect
cycles (R_ENABLE = 0). For FIFO interface, ASADS/ASRE acts as SRE with NO deselect cycles (R_ENABLE = 1).
− In this figure W_LTNCY = 1, CE_EXT = 0, R_ENABLE = 0, and SSEL = 1.
B AAOE/ASOE, and AAWE/ASWE operate as ASOE, and ASWE, respectively, during programmable synchronous interface accesses.
SM320C6455-EP
FIXED-POINT DIGITAL SIGNAL PROCESSOR
SPRS462B – SEPTEMBER 2007 – REVISED JANUARY 2008
Figure 7-38. Programmable Synchronous Interface Write Timing for EMIFA (With Write Latency = 1)
(A)
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