LPC2292_2294 NXP Semiconductors, LPC2292_2294 Datasheet - Page 23

• Manufacturer Part Number: LPC2292_2294
• Description: The LPC2292/2294 microcontrollers are based on a 16/32-bit ARM7TDMI-S CPU withreal-time emulation and embedded trace support, together with 256 kB of embeddedhigh-speed flash memory
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC2292_2294
Product data sheet
6.15.2 Features available in LPC2292/2294/01 only
6.16.1 Features
6.17.1 Features
6.16 Watchdog timer
6.17 Real-time clock
The LPC2292/2294/01 can count external events on one of the capture inputs if the
external pulse lasts at least one half of the period of the PCLK. In this configuration,
unused capture lines can be selected as regular timer capture inputs, or used as external
interrupts.
The purpose of the watchdog is to reset the microcontroller within a reasonable amount of
time if it enters an erroneous state. When enabled, the watchdog will generate a system
reset if the user program fails to ‘feed’ (or reload) the watchdog within a predetermined
amount of time.
The Real-Time Clock (RTC) is designed to provide a set of counters to measure time
when normal or idle operating mode is selected. The RTC has been designed to use little
power, making it suitable for battery powered systems where the CPU is not running
continuously (Idle mode).
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Timer can count cycles of either the peripheral clock (PCLK) or an externally supplied
clock.
When counting cycles of an externally supplied clock, only one of the timer’s capture
inputs can be selected as the timer’s clock. The rate of such a clock is limited to
PCLK / 4. Duration of HIGH/LOW levels on the selected CAP input cannot be shorter
than 1 / (2PCLK).
Internally resets chip if not periodically reloaded.
Debug mode.
Enabled by software but requires a hardware reset or a watchdog reset/interrupt to be
disabled.
Incorrect/incomplete feed sequence causes reset/interrupt if enabled.
Flag to indicate watchdog reset.
Programmable 32-bit timer with internal prescaler.
Selectable time period from (T
T
Measures the passage of time to maintain a calendar and clock.
Ultra-low power design to support battery powered systems.
Provides Seconds, Minutes, Hours, Day of Month, Month, Year, Day of Week, and
Day of Year.
Programmable Reference Clock Divider allows adjustment of the RTC to match
various crystal frequencies.
cy(PCLK)
 4.
All information provided in this document is subject to legal disclaimers.
16/32-bit ARM microcontrollers with external memory interface
Rev. 8 — 8 June 2011
cy(PCLK)
 256  4) to (T
cy(PCLK)
LPC2292/2294
 2
32
 4) in multiples of
© NXP B.V. 2011. All rights reserved.
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