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LPC2478 Developer’s Kit - User’s Guide Page 12
Copyright 2011 © Embedded Artists AB
3.1.9 Expansion Connectors
The LPC2478 OEM Board integrated the core part of a typical LPC2478 board design with a
reasonable large amount of external memories. Almost all signals of LPC2478 are available on the 200
pos, 0.6mm pitch expansion connector (SODIMM-200 format).
3.2 Memory Layout
The external memory controller on the LPC2478 defines eight memory regions, named: CS0, CS1,
CS2, CS3, DYCS0, DYCS1, DYCS2, and DYCS3. Of these eight, three memory areas are used by the
LPC2478 OEM Board . These are:

CS0 (address range: 0x8000 0000 – 0x80FF FFFF)
An external NOR FLASH (32 MBit = 4 MByte in size) is addressed.

CS1 (address range: 0x8100 0000 – 0x81FF FFFF)
An external NAND FLASH (1 GBit = 128 MByte in size) is addressed.

DYCS0 (address range: 0xA000 0000 – 0xAFFF FFFF)
An external SDRAM (256 MBit = 32 MByte in size) is addressed.
These three memory regions cannot be used by external devices. CS2 and DYCS1 are however free
for external use via the buffered memory interface. Both address and data busses are buffered.
3.3 Usage of CPU Pins
Almost all pins of the LPC2478 are directly available on the expansion connectors. Only in a few cases
are pins used for dedicated functionality like Ethernet interface and chip select signals. Such pins are
not available on the expansion connector. The table below lists all pins and their possible restrictions.
Pin Available on expansion
connector
P0.0-P0.26 Yes
P0.27- P0.28 Yes, but I2C E2PROM
connected to these pins.
P0.29-P0.31 Yes
USBB- Yes
P1.0-P1.1,
P1.4,
P1.8-P1.10,
P1.14-P1.17
No, connected to Ethernet
PHY
P1.2-P1.3,
P1.5-P1.7,
P1.11-P1.13,
P1.18- P1.26-
P1.31
Yes
P2.0-P2.15,
P2.19,
P2.21-P2.23,
P2.25-P2.27
Yes
P2.16-P2.17 Yes, but used as RAS/CAS
and only available as outputs
via a buffer
P2.18,
P2.20,
P2.24
No, used as
CLKOUT0/DYCS0/CKE0 for
external SDRAM
P2.28-P2.29 Yes, but used as
DQM0/DQM1 (for external
SDRAM) and only available
as outputs via a buffer
P2.30-P2.31 Yes, but used as
DQM2/DQM3 (on 32-bit data
bus version)
P3.0-P3.15 Yes, but used as data bus
and only available via data
bus buffer
P3.16-P3.31 Yes. On 32-bit data bus
versions these pins are used
for upper 16 bits of the data
bus and are only available
via the data bus buffer
P4.0-P4.23 Yes, but used as address
bus and only available as
outputs via buffers
P4.24-P4.27 Yes, but used as