UM10237_2 © NXP B.V. 2008. All rights reserved.
User manual Rev. 02 — 19 December 2008 96 of 792
NXP Semiconductors UM10237
Chapter 5: LPC24XX External Memory Controller (EMC)

Symbol "a_b" in the following figures refers to the highest order address line in the data

bus. Symbol "a_m" refers to the highest order address line of the memory chip used in the

external memory interface.

If the external memory is used as external boot memory for flashless devices, refer to

Section 8–6 on how to connect the EMC. The memory bank width for memory banks 1

and 2 is determined by the setting of the two BOOT1/0 pins.

11.1 32-bit wide memory bank connection

a. 32 bit wide memory bank interfaced to four 8 bit memory chips

b. 32 bit wide memory bank interfaced to two 16 bit memory chips

A[a_b:2]
BLS[1]
D[15:8]
CE
OE
WE
IO[7:0]
A[a_m:0]
BLS[0]
D[7:0]
CE
OE
WE
IO[7:0]
A[a_m:0]
OE
CS
BLS[3]
D[31:24]
CE
OE
WE
IO[7:0]
A[a_m:0]
BLS[2]
D[23:16]
CE
OE
WE
IO[7:0]
A[a_m:0]
OE
CS
WE
CE
OE
WE
UB
LB
IO[15:0]
A[a_m:0]
D[31:16]
BLS[2]
CE
OE
WE
UB
LB
IO[15:0]
A[a_m:0]
D[15:0]
BLS[0]
A[a_b:2]
BLS[3] BLS[1]