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UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008
134 of 792
NXP Semiconductors
UM10237
Chapter 8: LPC24XX Pin configuration
P4[24]/OE
I/O
P4[24] —
General purpose digital input/output pin.
O
OE —
LOW active Output Enable signal.
P4[25]/WE
I/O
P4[25] —
General purpose digital input/output pin.
O
WE —
LOW active Write Enable signal.
P4[26]/BLS0
K13
I/O
P4[26] —
General purpose digital input/output pin.
O
BLS0 —
LOW active Byte Lane select signal 0.
P4[27]/BLS1
F14
I/O
P4[27] —
General purpose digital input/output pin.
O
BLS1 —
LOW active Byte Lane select signal 1.
P4[28]/MAT2[0]/
TXD3
D10
I/O
P4[28] —
General purpose digital input/output pin.
O
MAT2[0] —
Match output for Timer 2, channel 0.
O
TXD3 —
Transmitter output for UART3.
P4[29]/MAT2[1]/
RXD3
I/O
P4[29] —
General purpose digital input/output pin.
O
MAT2[1] —
Match output for Timer 2, channel 1.
I
RXD3 —
Receiver input for UART3.
P4[30]/CS0
I/O
P4[30] —
General purpose digital input/output pin.
O
CS0 —
LOW active Chip Select 0 signal.
P4[31]/CS1
I/O
P4[31] —
General purpose digital input/output pin.
O
CS1 —
LOW active Chip Select 1 signal.
ALARM
H5
O
ALARM —
RTC controlled output. This is a 1.8 V pin. It goes HIGH when a RTC
alarm is generated.
USB_D
−
2
N2
I/O
USB_D
−
2 —
USB port 2 bidirectional D
−
line.
DBGEN
E5
I
DBGEN —
JTAG interface control signal. Also used for boundary scan.
TDO
B1
O
TDO —
Test Data Out for JTAG interface.
TDI
C3
I
TDI —
Test Data In for JTAG interface.
TMS
C2
I
TMS —
Test Mode Select for JTAG interface.
TRST
I
TRST —
Test Reset for JTAG interface.
TCK
D2
I
TCK —
Test Clock for JTAG interface. This clock must be slower than
1
⁄
6
of the
CPU clock (CCLK) for the JTAG interface to operate.
RTCK
C4
I/O
RTCK —
JTAG interface control signal.
Note:
LOW on this pin while RESET is LOW enables ETM pins (P2[9:0]) to
operate as Trace port after reset.
RSTOUT
H2
O
RSTOUT —
This is a 3.3 V pin. LOW on this pin indicates UM10237 being in
Reset state.
RESET
I
external reset input:
A LOW on this pin resets the device, causing I/O ports and
peripherals to take on their default states, and processor execution to begin at
address 0. TTL with hysteresis, 5 V tolerant.
XTAL1
L2
I
Input to the oscillator circuit and internal clock generator circuits.
XTAL2
K4
O
Output from the oscillator amplifier.
RTCX1
J2
I
Input to the RTC oscillator circuit.
RTCX2
J3
O
Output from the RTC oscillator circuit.
Table 120. Pin description
…continued
Symbol
Ball
Type
Description