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UM10503
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© NXP B.V. 2015. All rights reserved.
User manual
Rev. 2.1 — 10 December 2015
615 of 1441
NXP Semiconductors
UM10503
Chapter 23: LPC43xx/LPC43Sxx External Memory Controller (EMC)
[1]
Extended wait and page mode cannot be selected simultaneously.
[2]
EMC may perform burst read access even when the buffer enable bit is cleared.
5:4
-
-
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
-
6
PC
Chip select polarity.
The value of the chip select polarity on power-on reset is 0.
0
0
Active LOW chip select.
1
Active HIGH chip select.
7
PB
Byte lane state.
The byte lane state bit, PB, enables different types of memory to
be connected. For byte-wide static memories the BLSn[3:0]
signal from the EMC is usually connected to WE (write enable).
In this case for reads all the BLSn[3:0] bits must be HIGH. This
means that the byte lane state (PB) bit must be LOW.
16 bit wide static memory devices usually have the BLSn[3:0]
signals connected to the UBn and LBn (upper byte and lower
byte) signals in the static memory. In this case a write to a
particular byte must assert the appropriate UBn or LBn signal
LOW. For reads, all the UB and LB signals must be asserted
LOW so that the bus is driven. In this case the byte lane state
(PB) bit must be HIGH.
Remark:
When PB is set to 0, the WE signal is undefined or 0.
You must set PB to 1, to use the WE signal.
0
0
High. For reads all the bits in BLSn[3:0] are HIGH. For writes the
respective active bits in BLSn[3:0] are LOW (POR reset value).
1
Low. For reads the respective active bits in BLSn[3:0] are LOW.
For writes the respective active bits in BLSn[3:0] are LOW.
8
EW
Extended wait.
Extended wait (EW) uses the StaticExtendedWait register to
time both the read and write transfers rather than the
StaticWaitRd and StaticWaitWr registers. This enables much
longer transactions.
0
0
Disabled. Extended wait disabled (POR reset value).
1
Enabled. Extended wait enabled.
18:9
-
-
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
-
19
B
Buffer enable
.
0
0
Disabled. Buffer disabled (POR reset value).
1
Enabled. Buffer enabled.
20
P
Write protect.
0
0
None. Writes not protected (POR reset value).
1
Protect. Write protected.
31:21 -
-
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
-
Table 436. Static Memory Configuration registers (STATICCONFIG[0:3], address 0x4000 5200
(STATICCONFIG0) to 0x4000 5260 (STATICCONFIG3)) bit description
Bit
Symbol
Value Description
Reset
value