LM3S101-CRN20-XNPP ETC1 [List of Unclassifed Manufacturers], LM3S101-CRN20-XNPP Datasheet - Page 22

• Manufacturer Part Number: LM3S101-CRN20-XNPP
• Description: Microcontroller
• Manufacturer: ETC1 [List of Unclassifed Manufacturers]

1.4.4
1.4.4.1
1.4.4.2
March 22, 2006
The LM3S101 controller provides two independent integrated analog comparators that can be
configured to drive an output or generate an interrupt.
A comparator can compare a test voltage against any one of these voltages:
The comparator can provide its output to a device pin, acting as a replacement for an analog
comparator on the board, or it can be used to signal the application via interrupts to cause it to
start capturing a sample sequence. The interrupt generation logic is separate.
Serial Communications Peripherals
The LM3S101 controller supports both asynchronous and synchronous serial communications
with one fully programmable 16C550-type UART and SSI serial communications.
UART (Section 11 on page 182)
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 LM3S101 controller includes one fully programmable 16C550-type UART that supports data
transfer speeds up to 460.8 Kbps. (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 (Section 12 on page 218)
Synchronous Serial Interface (SSI) is a four-wire bi-directional communications interface.
The LM3S101 controller SSI module provides the functionality for synchronous serial
communications with peripheral devices, and can be configured to use the Freescale SPI, National
Semiconductor MICROWIRE, or TI synchronous serial interface frame formats. The size of the
data frame is also configurable, and can be set to be 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.
The Inter-Integrated Circuit (I
design (a serial data line SDL and a serial clock line SCL).
The I
networking devices, LCDs, tone generators, and so on. The I
testing and diagnostic purposes in product development and manufacture.
An individual external reference voltage
A shared single external reference voltage
A shared internal reference voltage
2
C bus interfaces to external I
2
C) bus provides bi-directional data transfer through a two-wire
2
Preliminary
C devices such as serial memory (RAMs and ROMs),
2
C bus may also be used for system
LM3S101 Data Sheet
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