lpc4310 NXP Semiconductors, lpc4310 Datasheet - Page 44

• Manufacturer Part Number: lpc4310
• Description: Lpc4350/30/20/10 32-bit Arm Cortex-m4/m0 Mcu; Up To 264 Kb Sram; Ethernet; Two High-speed Usbs; Advanced Configurable Peripherals
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC4350_30_20_10
Objective data sheet
7.14.1.1 Features
7.14.1 General purpose 32-bit timers/external event counters
7.14.2 Motor control PWM
7.14.3 Quadrature Encoder Interface (QEI)
7.14 Counter/timers and motor control
The LPC4350/30/20/10 include four 32-bit timer/counters. The timer/counter is designed
to count cycles of the system derived clock or an externally-supplied clock. It can
optionally generate interrupts, generate timed DMA requests, or perform other actions at
specified timer values, based on four match registers. Each timer/counter also includes
two capture inputs to trap the timer value when an input signal transitions, optionally
generating an interrupt.
The motor control PWM is a specialized PWM supporting 3-phase motors and other
combinations. Feedback inputs are provided to automatically sense rotor position and use
that information to ramp speed up or down. An abort input is also provided that causes the
PWM to immediately release all motor drive outputs. At the same time, the motor control
PWM is highly configurable for other generalized timing, counting, capture, and compare
applications.
A quadrature encoder, also known as a 2-channel incremental encoder, converts angular
displacement into two pulse signals. By monitoring both the number of pulses and the
relative phase of the two signals, the user can track the position, direction of rotation, and
velocity. In addition, a third channel, or index signal, can be used to reset the position
counter. The quadrature encoder interface decodes the digital pulses from a quadrature
encoder wheel to integrate position over time and determine direction of rotation. In
addition, the QEI can capture the velocity of the encoder wheel.
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A 32-bit timer/counter with a programmable 32-bit prescaler.
Counter or timer operation.
Two 32-bit capture channels per timer, that can take a snapshot of the timer value
when an input signal transitions. A capture event may also generate an interrupt.
Four 32-bit match registers that allow:
– Continuous operation with optional interrupt generation on match.
– Stop timer on match with optional interrupt generation.
– Reset timer on match with optional interrupt generation.
Up to four external outputs corresponding to match registers, with the following
capabilities:
– Set LOW on match.
– Set HIGH on match.
– Toggle on match.
– Do nothing on match.
Up to two match registers can be used to generate timed DMA requests.
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 29 October 2010
32-bit ARM Cortex-M4/M0 microcontroller
LPC4350/30/20/10
© NXP B.V. 2010. All rights reserved.
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