LM3S5737 Datasheet, PDF (48/833 Pages) Texas Instruments – Stellaris® LM3S5737 Microcontroller

Architectural Overview
1.4.4.4
1.4.4.5
1.4.5
1.4.5.1
The I²C bus interfaces to external I²C devices such as serial memory (RAMs and ROMs), networking
devices, LCDs, tone generators, and so on. The I²C bus may also be used for system testing and
diagnostic purposes in product development and manufacture.
The LM3S5737 controller includes two I²C modules that provide the ability to communicate to other
IC devices over an I²C bus. The I²C bus supports devices that can both transmit and receive (write
and read) data.
Devices on the I²C bus can be designated as either a master or a slave. Each I²C module supports
both sending and receiving data as either a master or a slave, and also supports the simultaneous
operation as both a master and a slave. The four I²C modes are: Master Transmit, Master Receive,
Slave Transmit, and Slave Receive.
A Stellaris I²C module can operate at two speeds: Standard (100 Kbps) and Fast (400 Kbps).
Both the I²C master and slave can generate interrupts. The I²C master generates interrupts when
a transmit or receive operation completes (or aborts due to an error). The I²C slave generates
interrupts when data has been sent or requested by a master.
USB (see page 659)
Universal Serial Bus (USB) is a serial bus standard designed to allow peripherals to be connected
and disconnected using a standardized interface without rebooting the system.
The LM3S5737 controller supports the USB 2.0 full-speed configuration with Device or USB Host
mode. The specified throughput for a USB 2.0 full-speed controller is 12 Mbps.
Controller Area Network (see page 613)
Controller Area Network (CAN) is a multicast shared serial-bus standard for connecting electronic
control units (ECUs). CAN was specifically designed to be robust in electromagnetically noisy
environments and can utilize a differential balanced line like RS-485 or a more robust twisted-pair
wire. Originally created for automotive purposes, now it is used in many embedded control
applications (for example, industrial or medical). Bit rates up to 1Mb/s are possible at network lengths
below 40 meters. Decreased bit rates allow longer network distances (for example, 125 Kb/s at
500m).
A transmitter sends a message to all CAN nodes (broadcasting). Each node decides on the basis
of the identifier received whether it should process the message. The identifier also determines the
priority that the message enjoys in competition for bus access. Each CAN message can transmit
from 0 to 8 bytes of user information. The LM3S5737 includes one CAN unit.
System Peripherals
Programmable GPIOs (see page 348)
General-purpose input/output (GPIO) pins offer flexibility for a variety of connections.
The Stellaris GPIO module is comprised of eight physical GPIO blocks, each corresponding to an
individual GPIO port. The GPIO module is FiRM-compliant (compliant to the ARM Foundation IP
for Real-Time Microcontrollers specification) and supports 27-61 programmable input/output pins.
The number of GPIOs available depends on the peripherals being used (see “Signal
Tables” on page 754 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.
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November 17, 2011
Texas Instruments-Production Data