LM3S2965 Datasheet, PDF (32/542 Pages) List of Unclassifed Manufacturers – Microcontroller

Architectural Overview
1.4.2.2
1.4.3
1.4.3.1
1.4.3.2
wave is modulated to encode an analog signal. Typical applications include switching power supplies
and motor control.
On the LM3S2965, PWM motion control functionality can be achieved through dedicated, flexible
motion control hardware (the PWM pins) or through the motion control features of the general-purpose
timers (using the CCP pins).
PWM Pins (see page 458)
The LM3S2965 PWM module consists of three PWM generator blocks and a control block. Each
PWM generator block contains one timer (16-bit down or up/down counter), two comparators, a
PWM signal generator, a dead-band generator, and an interrupt/ADC-trigger selector. The control
block determines the polarity of the PWM signals, and which signals are passed through to the pins.
Each PWM generator block produces two PWM signals that can either be independent signals or
a single pair of complementary signals with dead-band delays inserted. The output of the PWM
generation blocks are managed by the output control block before being passed to the device pins.
CCP Pins (see page 208)
The General-Purpose Timer Module's CCP (Capture Compare PWM) pins are software programmable
to support a simple PWM mode with a software-programmable output inversion of the PWM signal.
QEI (see page 489)
A quadrature encoder, also known as a 2-channel incremental encoder, converts linear displacement
into a pulse signal. By monitoring both the number of pulses and the relative phase of the two signals,
you can track the position, direction of rotation, and speed. In addition, a third channel, or index
signal, can be used to reset the position counter.
The Stellaris quadrature encoder with index (QEI) module interprets the code produced by a
quadrature encoder wheel to integrate position over time and determine direction of rotation. In
addition, it can capture a running estimate of the velocity of the encoder wheel. The LM3S2965
microcontroller includes two QEI modules, which enables control of two motors at the same time.
Serial Communications Peripherals
The LM3S2965 controller supports both asynchronous and synchronous serial communications
with three fully programmable 16C550-type UARTs, two SSI modules, two I²C modules, and two
CAN units.
UART (see page 291)
A Universal Asynchronous Receiver/Transmitter (UART) is an integrated circuit used for RS-232C
serial communications, containing a transmitter (parallel-to-serial converter) and a receiver
(serial-to-parallel converter), each clocked separately.
The LM3S2965 controller includes three fully programmable 16C550-type UARTs that support data
transfer speeds up to 460.8 Kbps. In addition, each UART is capable of supporting IrDA. (Although
similar in functionality to a 16C550 UART, it is not register-compatible.)
Separate 16x8 transmit (TX) and 16x12 receive (RX) FIFOs reduce CPU interrupt service loading.
The UART can generate individually masked interrupts from the RX, TX, modem status, and error
conditions. The module provides a single combined interrupt when any of the interrupts are asserted
and are unmasked.
SSI (see page 331)
Synchronous Serial Interface (SSI) is a four-wire bi-directional communications interface.
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June 04, 2007
Preliminary