USART Registers: UART Mode

UxTCTL, USART Transmit Control Register

7

6

5

4

3

2

1

0

Unused

CKPL

SSELx

URXSE

TXWAKE

Unused

TXEPT

rw−0

rw−0

rw−0

rw−0

rw−0

rw−0

rw−0

rw−1

Unused

Bit 7

Unused

CKPL

Bit 6

Clock polarity select

 

 

0

UCLKI = UCLK

 

 

1

UCLKI = inverted UCLK

SSELx

Bits

Source select. These bits select the BRCLK source clock.

 

5-4

00

UCLKI

 

 

01

ACLK

 

 

10

SMCLK

 

 

11

SMCLK

URXSE

Bit 3

UART receive start-edge. The bit enables the UART receive start-edge

 

 

feature.

 

 

0

Disabled

 

 

1

Enabled

TXWAKE

Bit 2

Transmitter wake

 

 

0

Next character transmitted is data

 

 

1

Next character transmitted is an address

Unused

Bit 1

Unused

TXEPT

Bit 0

Transmitter empty flag

 

 

0

UART is transmitting data and/or data is waiting in UxTXBUF

 

 

1

Transmitter shift register and UxTXBUF are empty or SWRST=1

USART Peripheral Interface, UART Mode

13-23

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Texas Instruments MSP430x1xx manual UxTCTL, Usart Transmit Control Register, SSELx

MSP430x1xx specifications

The Texas Instruments MSP430x1xx series is a family of ultra-low-power microcontrollers that are highly regarded in the embedded systems community for their versatility and performance. Designed for applications ranging from portable instrumentation to low-power industrial devices, the MSP430x1xx combines flexibility and efficiency with advanced features tailored for energy-sensitive applications.

One of the standout characteristics of the MSP430x1xx is its ultra-low-power operation. This series offers several low-power modes that can significantly extend battery life in portable devices. The microcontroller can be in active mode, low-power mode, or even in a deep sleep state, allowing developers to optimize power consumption based on the application's requirements. In fact, some configurations can operate at just a few microamps, making it ideal for battery-operated devices.

Another key feature is the 16-bit RISC architecture that provides powerful processing capabilities while maintaining a low power profile. The MSP430x1xx series supports a maximum clock speed of 16 MHz, allowing for efficient task execution while consuming minimal energy. This architecture ensures that programs run smoothly while the microcontroller remains energy efficient.

The MSP430x1xx is equipped with various integrated peripherals, including analog-to-digital converters (ADCs), timers, and communication interfaces like UART, SPI, and I2C. The inclusion of a powerful ADC enables the microcontroller to handle sensor readings with high accuracy, making it suitable for applications like environmental monitoring and medical devices. The integrated timers provide essential functionality for real-time applications, allowing for event-driven programming and precise timing control.

Memory options in the MSP430x1xx series are also robust, with configurations offering flash memory sizes from 1 KB to 64 KB. This flexibility allows developers to choose the optimal memory size for their specific applications, accommodating a wide range of requirements.

Additionally, the MSP430x1xx microcontrollers are designed with a wide operating voltage range, typically from 1.8V to 3.6V, making them compatible with various power sources and further enhancing their usability in diverse applications.

In summary, the Texas Instruments MSP430x1xx series of microcontrollers is an excellent choice for developers seeking low-power, high-performance solutions for embedded applications. With an efficient architecture, a rich set of peripherals, and flexible memory options, these microcontrollers are positioned to meet the growing demands of modern electronic designs, particularly in battery-powered and energy-sensitive applications.