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UM10503
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© NXP B.V. 2015. All rights reserved.
User manual
Rev. 2.1 — 10 December 2015
617 of 1441
NXP Semiconductors
UM10503
Chapter 23: LPC43xx/LPC43Sxx External Memory Controller (EMC)
[1]
The reset value depends on the boot mode. See
Section 5.3.4.2 “EMC boot modes”
23.7.25 Static Memory Page Mode Read Delay registers
These registers enable you to program the delay for asynchronous page mode sequential
accesses. It is recommended that these registers are modified during system initialization,
or when there are no current or outstanding transactions. This can be ensured by waiting
until the EMC is idle, and then entering low-power, or disabled mode. This register is
accessed with one wait state.
23.7.26 Static Memory Write Delay registers
These registers enable you to program the delay from the chip select to the write access.
It is recommended that these registers are modified during system initialization, or when
there are no current or outstanding transactions. This can be ensured by waiting until the
EMC is idle, and then entering low-power, or disabled mode.These registers are not used
if the extended wait (EW) bit is enabled in the StaticConfig register. These registers are
accessed with one wait state.
Table 439. Static Memory Read Delay registers (STATICWAITRD[0:3], address 0x4000 520C
(STATICWAITRD0) to 0x4000 526C (STATICWAITRD3)) bit description
Bit
Symbol
Description
Reset
value
4:0
WAITRD
Non-page mode read wait states or asynchronous page mode read first
access wait state.
Non-page mode read or asynchronous page mode read, first read only:
0x0 - 0x1E = (n + 1) EMC_CCLK cycles for read accesses. For
non-sequential reads, the wait state time is ( 1) x
tEMC_CCLK.
0x1F = 32 EMC_CCLK cycles for read accesses (POR reset value).
0x1F
31:5
-
Reserved, user software should not write ones to reserved bits. The
value read from a reserved bit is not defined.
-
Table 440. Static Memory Page Mode Read Delay registers (STATICWAITPAGE[0:3], address
0x4000 5210 (STATICWAITPAGE0) to 0x4000 5270 (STATICWAITPAGE3)) bit
description
Bit
Symbol
Description
Reset
value
4:0
WAITPAGE
Asynchronous page mode read after the first read wait states.
Number of wait states for asynchronous page mode read accesses
after the first read:
0x0 - 0x1E = (n+ 1) EMC_CCLK cycle read access time. For
asynchronous page mode read for sequential reads, the wait state
time for page mode accesses after the first read is (WA 1)
x tEMC_CCLK.
0x1F = 32 EMC_CCLK cycle read access time (POR reset value).
0x1F
31:5
-
Reserved, user software should not write ones to reserved bits. The
value read from a reserved bit is not defined.
-