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Functional Overview
2-28
Copyright © 2006 ARM Limited. All rights reserved.
ARM DDI 0389B
Read data output by the memory device is also registered on the rising edge of
smc_mclk0n
, equivalent to the falling edge of
smc_mclk0
, for asynchronous reads. For
synchronous reads, read data is registered using the fed back clock,
smc_fbclk_in
. For
synchronous and asynchronous accesses, the data is then pushed onto the read data
FIFO to be returned by the SMC interface.
This subsection describes:
•
Asynchronous read
•
Asynchronous read in multiplexed-mode
on page 2-29
•
Asynchronous write
on page 2-30
•
Asynchronous write in multiplexed-mode
on page 2-31
•
Asynchronous page mode read
on page 2-31
•
Synchronous burst read
on page 2-32
•
Synchronous burst read in multiplexed-mode
on page 2-34
•
Synchronous burst write
on page 2-35
•
Synchronous burst write in multiplexed-mode
on page 2-36
•
Synchronous read and asynchronous write
on page 2-37.
Asynchronous read
Table 2-2 and Table 2-3 list the smc_opmode0_<0-3> and SRAM Register settings. See
Register summary
on page 3-3.
Figure 2-14 on page 2-29 shows a single asynchronous read transfer with an initial
access time, t
RC
, of three cycles and an output enable assertion delay, t
CEOE
, of one
cycle.
Table 2-2 Asynchronous read opmode chip register settings
Field
mw
rd_sync
rd_bl
wr_sync
wr_bl
baa
adv
bls
ba
Value
-
b0
b000
-
-
-
-
-
-
Table 2-3 Asynchronous read SRAM cycles register settings
Field
t_rc
t_wc
t_ceoe
t_wp
t_pc
t_tr
Value
b0011
-
b001
-
-
-
Summary of Contents for PrimeCell PL241
Page 20: ...Introduction 1 6 Copyright 2006 ARM Limited All rights reserved ARM DDI 0389B ...
Page 60: ...Functional Overview 2 40 Copyright 2006 ARM Limited All rights reserved ARM DDI 0389B ...
Page 94: ...Device Driver Requirements 5 6 Copyright 2006 ARM Limited All rights reserved ARM DDI 0389B ...
Page 104: ...Signal Descriptions A 10 Copyright 2006 ARM Limited All rights reserved ARM DDI 0389B ...
Page 110: ...Glossary Glossary 6 Copyright 2006 ARM Limited All rights reserved ARM DDI 0389B ...