Call

Instruction Set

CALL	Subroutine
Syntax	CALL	dst
Operation	dst	−> tmp	dst is evaluated and stored
	SP − 2	−> SP
	PC	−> @SP	PC updated to TOS
	tmp	−> PC	dst saved to PC
Description	A subroutine call is made to an address anywhere in the 64K address space.
	All addressing modes can be used. The return address (the address of the
	following instruction) is stored on the stack. The call instruction is a word
	instruction.
Status Bits	Status bits are not affected.
Example	Examples for all addressing modes are given.
	CALL	#EXEC	; Call on label EXEC or immediate address (e.g. #0A4h)
			; SP−2 → SP, PC+2 → @SP, @PC+ → PC
	CALL	EXEC	; Call on the address contained in EXEC
			; SP−2 → SP, PC+2 → @SP, X(PC) → PC
			; Indirect address
	CALL	&EXEC	; Call on the address contained in absolute address
			; EXEC
			; SP−2 → SP, PC+2 → @SP, X(0) → PC
			; Indirect address
	CALL	R5	; Call on the address contained in R5
			; SP−2 → SP, PC+2 → @SP, R5 → PC
			; Indirect R5
	CALL	@R5	; Call on the address contained in the word
			; pointed to by R5
			; SP−2 → SP, PC+2 → @SP, @R5 → PC
			; Indirect, indirect R5
	CALL	@R5+	; Call on the address contained in the word
			; pointed to by R5 and increment pointer in R5.
			; The next time—S/W flow uses R5 pointer—
			; it can alter the program execution due to
			; access to next address in a table pointed to by R5
			; SP−2 → SP, PC+2 → @SP, @R5 → PC
			; Indirect, indirect R5 with autoincrement
	CALL	X(R5)	; Call on the address contained in the address pointed
			; to by R5 + X (e.g. table with address starting at X)

; X can be an address or a label

; SP−2 → SP, PC+2 → @SP, X(R5) → PC ; Indirect, indirect R5 + X

RISC 16−Bit CPU

3-29

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 Call

Models: MSP430x1xx

Description

Status Bits

Example

MSP430x1xx specifications