LM3S1332 Luminary Micro, Inc, LM3S1332 Datasheet - Page 31

• Manufacturer Part Number: LM3S1332
• Description: Lm3s1332 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

1.4.4.1
1.4.4.2
1.4.5
1.4.5.1
1.4.5.2
July 26, 2008
UART (see page 293)
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 LM3S1332 controller includes two fully programmable 16C550-type UARTs that support data
transfer speeds up to 3.125 Mbps. (Although similar in functionality to a 16C550 UART, it is not
register-compatible.) In addition, each UART is capable of supporting IrDA.
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 334)
Synchronous Serial Interface (SSI) is a four-wire bi-directional communications interface.
The LM3S1332 controller includes one SSI module that provides the functionality for synchronous
serial communications with peripheral devices, and can be configured to use the Freescale SPI,
MICROWIRE, or TI synchronous serial interface frame formats. The size of the data frame is also
configurable, and can be set between 4 and 16 bits, inclusive.
The SSI module performs serial-to-parallel conversion on data received from a peripheral device,
and parallel-to-serial conversion on data transmitted to a peripheral device. The TX and RX paths
are buffered with internal FIFOs, allowing up to eight 16-bit values to be stored independently.
The SSI module can be configured as either a master or slave device. As a slave device, the SSI
module can also be configured to disable its output, which allows a master device to be coupled
with multiple slave devices.
The SSI module also includes a programmable bit rate clock divider and prescaler to generate the
output serial clock derived from the SSI module's input clock. Bit rates are generated based on the
input clock and the maximum bit rate is determined by the connected peripheral.
System Peripherals
Programmable GPIOs (see page 159)
General-purpose input/output (GPIO) pins offer flexibility for a variety of connections.
The Stellaris
individual GPIO port. The GPIO module is FiRM-compliant (compliant to the ARM Foundation IP
for Real-Time Microcontrollers specification) and supports 29-57 programmable input/output pins.
The number of GPIOs available depends on the peripherals being used (see “Signal Tables” on page
386 for the signals available to each GPIO pin).
The GPIO module features programmable interrupt generation as either edge-triggered or
level-sensitive on all pins, programmable control for GPIO pad configuration, and bit masking in
both read and write operations through address lines. Pins configured as digital inputs are
Schmitt-triggered.
Four Programmable Timers (see page 201)
Programmable timers can be used to count or time external events that drive the Timer input pins.
The Stellaris
block provides two 16-bit timers/counters that can be configured to operate independently as timers
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GPIO module is comprised of eight physical GPIO blocks, each corresponding to an
General-Purpose Timer Module (GPTM) contains four GPTM blocks. Each GPTM
Preliminary
LM3S1332 Microcontroller
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