Interrupt Processing | Texas Instruments MSP430x1xx guide

System Reset and Initialization

Each individual peripheral interrupt is discussed in the associated peripheral module chapter in this manual.

2.2.3Interrupt Processing

When an interrupt is requested from a peripheral and the peripheral interrupt enable bit and GIE bit are set, the interrupt service routine is requested. Only the individual enable bit must be set for (non)-maskable interrupts to be requested.

Interrupt Acceptance

The interrupt latency is 6 cycles, starting with the acceptance of an interrupt request, and lasting until the start of execution of the first instruction of the interrupt-service routine, as shown in Figure 2−7. The interrupt logic executes the following:

1)Any currently executing instruction is completed.

2)The PC, which points to the next instruction, is pushed onto the stack.

3)The SR is pushed onto the stack.

4)The interrupt with the highest priority is selected if multiple interrupts occurred during the last instruction and are pending for service.

5)The interrupt request flag resets automatically on single-source flags. Multiple source flags remain set for servicing by software.

6)The SR is cleared with the exception of SCG0, which is left unchanged. This terminates any low-power mode. Because the GIE bit is cleared, further interrupts are disabled.

7)The content of the interrupt vector is loaded into the PC: the program continues with the interrupt service routine at that address.

Figure 2−7. Interrupt Processing

Before

Interrupt

Item1

Item2

TOS

After

Interrupt

Item1

Item2

TOS

System Resets, Interrupts, and Operating Modes

2-11

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.

Texas Instruments MSP430x1xx manual Interrupt Processing, Interrupt Acceptance

Models: MSP430x1xx

2.2.3Interrupt Processing

Interrupt Acceptance

Figure 2−7. Interrupt Processing

MSP430x1xx specifications