Datasheet

Table Of Contents
LPC11CX2_CX4 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 3.1 — 15 May 2013 17 of 62
NXP Semiconductors
LPC11Cx2/Cx4
32-bit ARM Cortex-M0 microcontroller
Four programmable interrupt priority levels, with hardware priority level masking.
Software interrupt generation.
7.5.2 Interrupt sources
Each peripheral device has one interrupt line connected to the NVIC but may have several
interrupt flags. Individual interrupt flags may also represent more than one interrupt
source.
Any GPIO pin (total of 40 pins (LPC11C12/C14) or 36 pins (LPC11C22/C24)) regardless
of the selected function, can be programmed to generate an interrupt on a level, or rising
edge or falling edge, or both.
7.6 IOCONFIG block
The IOCONFIG block allows selected pins of the microcontroller to have more than one
function. Configuration registers control the multiplexers to allow connection between the
pin and the on-chip peripherals.
Peripherals should be connected to the appropriate pins prior to being activated and prior
to any related interrupt(s) being enabled. Activity of any enabled peripheral function that is
not mapped to a related pin should be considered undefined.
7.7 Fast general purpose parallel I/O
Device pins that are not connected to a specific peripheral function are controlled by the
GPIO registers. Pins may be dynamically configured as inputs or outputs. Multiple outputs
can be set or cleared in one write operation.
LPC11Cx2/Cx4 use accelerated GPIO functions:
GPIO registers are a dedicated AHB peripheral so that the fastest possible I/O timing
can be achieved.
Entire port value can be written in one instruction.
Additionally, any GPIO pin (total of 40 pins (LPC11C12/C14) or 36 pins (LPC11C22/C24))
providing a digital function can be programmed to generate an interrupt on a level, a rising
or falling edge, or both.
7.7.1 Features
Bit level port registers allow a single instruction to set or clear any number of bits in
one write operation.
Direction control of individual bits.
All GPIO pins default to inputs with pull-ups enabled after reset except for the I
2
C-bus
true open-drain pins PIO0_4 and PIO0_5.
Pull-up/pull-down resistor configuration can be programmed through the IOCONFIG
block for each GPIO pin (except PIO0_4 and PIO0_5).
All GPIO pins (except PIO0_4 and PIO0_5) are pulled up to 3.3 V (V
DD
= 3.3 V) if their
pull-up resistor is enabled in the IOCONFIG block.