External Interrupt Inputs; Register Description - Philips LPC214 Series User Manual

Philips Semiconductors
Volume 1

3.5 External interrupt inputs

The LPC2141/2/4/6/8 includes four External Interrupt Inputs as selectable pin functions.
The External Interrupt Inputs can optionally be used to wake up the processor from
Power-down mode.

3.5.1 Register description

The external interrupt function has four registers associated with it. The EXTINT register
contains the interrupt flags, and the EXTWAKEUP register contains bits that enable
individual external interrupts to wake up the microcontroller from Power-down mode. The
EXTMODE and EXTPOLAR registers specify the level and edge sensitivity parameters.
Table 8:
Name
EXTINT
User manual
True
True
MIN f = 10 MHz
OSC
MAX f = 25 MHz
OSC
(Figure 7, mode a and/or b)
Fig 7. F selection algorithm
OSC
External interrupt registers
Description
The External Interrupt Flag Register contains
interrupt flags for EINT0, EINT1, EINT2 and
EINT3. See Table
Rev. 01 — 15 August 2005
f selection
OSC
On-chip PLL used
in application?
False
ISP used for initial
code download?
False
External crystal
oscillator used?
False
MIN f = 1 MHz
OSC
MAX f = 50 MHz
OSC
(Figure 7, mode a)
9.
UM10139
Chapter 3: System Control Block
True
MIN f = 1 MHz
OSC
MAX f = 30 MHz
OSC
(Figure 7, mode b)
Access Reset Address
[1]
value
R/W 0 0xE01F C140
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
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