Digital I/O Operation

Interrupt Edge Select Registers P1IES, P2IES

Each PxIES bit selects the interrupt edge for the corresponding I/O pin.

Bit = 0: The PxIFGx flag is set with a low-to-high transition

Bit = 1: The PxIFGx flag is set with a high-to-low transition

Note: Writing to PxIESx

Writing to P1IES, or P2IES can result in setting the corresponding interrupt flags.

 

PxIESx

PxINx

PxIFGx

 

0 1

0

May be set

 

0 1

1

Unchanged

 

1 0

0

Unchanged

 

1 0

1

May be set

 

 

 

 

 

Interrupt Enable P1IE, P2IE

Each PxIE bit enables the associated PxIFG interrupt flag.

Bit = 0: The interrupt is disabled

Bit = 1: The interrupt is enabled

9.2.6Configuring Unused Port Pins

Unused I/O pins should be configured as I/O function, output direction, and left unconnected on the PC board, to reduce power consumption. The value of the PxOUT bit is don’t care, since the pin is unconnected. See chapter System Resets, Interrupts, and Operating Modes for termination unused pins.

9-6

Digital I/O

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Texas Instruments MSP430x1xx manual Interrupt Edge Select Registers P1IES, P2IES, Interrupt Enable P1IE, P2IE

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.