Samsung S3C2440A User Manual

Page 170

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S3C2440A RISC MICROPROCESSOR

MEMORY CONTROLLER

DEC.13, 2002

5-5

nWAIT PIN OPERATION

If the WAIT bit(WSn bit in BWSCON) corresponding to each memory bank is enabled, the nOE duration should be
prolonged by the external nWAIT pin while the memory bank is active. nWAIT is checked from tacc-1. nOE will be
de-asserted at the next clock after sampling nWAIT is high. The nWE signal have the same relation with nOE.

Tacs

Tcos

Tacc=4

HCLK

ADDR

nGCS

nOE

nWAIT

DATA(R)

Delayed

Sampling nWAIT

Figure 5-2. S3C2440A External nWAIT Timing Diagram (Tacc=4)

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