ep7312 Cirrus Logic, Inc., ep7312 Datasheet - Page 25

• Manufacturer Part Number: ep7312
• Description: High-performance, Low-power, System-on-chip With Sdram & Enhanced Digital Audio Interface
• Manufacturer: Cirrus Logic, Inc.

Static Memory Burst Write Cycle
DS508F1
EXPRDY
EXPCLK
WRITE
WORD
WORD
nMWE
nMOE
HALF
nCS
A
D
Note:
1. Four cycles are shown in the above diagram (minimum wait states, 1-1-1-1). This is the maximum number of consecutive
cycles that can be driven. The number of consecutive cycles can be programmed from 2 to 4, inclusively.
2. The cycle time can be extended by integer multiples of the clock period (22 ns at 45 MHz, 27 ns at 36 MHz, 54 ns at
18.432 MHz, and 77 ns at 13 MHz), by either driving EXPRDY low and/or by programming a number of wait states. EXPRDY is
sampled on the falling edge of EXPCLK before the data transfer. If low at this point, the transfer is delayed by one clock period
where EXPRDY is sampled again. EXPCLK need not be referenced when driving EXPRDY, but is shown for clarity.
3. Zero wait states for sequential writes is not permitted for memory devices which use nMWE pin, as this cannot be driven with
valid timing under zero wait state conditions.
4. Address, Data, Halfword, Word, and Write hold state until next cycle.
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HWd
WDd
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CSd
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Figure 10. Static Memory Burst Write Cycle Timing Measurement
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©
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Copyright Cirrus Logic, Inc. 2005
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(All Rights Reserved)
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High-Performance, Low-Power System on Chip
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EP7312
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