System Registers

value of the STACK register should be stored before use and restored after use. This register must point to the beginning of the stack in the RESET initialization routine before any CALL instruction or maskable interrupts can be used. CALL instructions increment R7 by 2., RET instructions decrement R7 by 2. The stack in MSP50P614/MSP50C614 is positively incremented.

4.2.11 String Register (STR)

The string register (STR) holds the length of the string used by all string instruc- tions. MOV instructions are used to load this register to define the length of a string. The value in this register is not altered after the execution of a string instruction. A value of zero in this register defines a string length of 2. Thus, a numerical value, ns, in the STR register, defines a string length of ns+2. The maximum string length is 32. Therefore, 0 nS 30 corresponds to actual string lengths from 2 to 32.

4.2.12 Status Register (STAT)

The status register (STAT) provides the storage of various single bit mode conditions and condition bits. As shown in Table 4±1, mode bits reside in the first 5 LSBs of the status register and can be independently set or reset with specific instructions. See section 4.6 for detail about these computational modes. Condition bits and flags are used for conditional branches, calls, and flag instructions. Flags and status condition bits are stored in the upper 10 bits of the 17 bit status register. MOV instructions provide the means for context saves and restores of the status register. The STAT should be initialized to 0000h after the processor resets.

The XSF and XZF flags are related to data flow to or from the internal data bus. If the destination of the transfer is an accumulator, then the SF, ZF, CF and OF flags are affected. If the destination of the transfer is Rx, the RCF and RZF flags are affected. If the destination of the transfer is through the internal databus, the XSF and XZF flags are affected. The SF flag is the sign flag and it is equal to the most significant bit of an accumulator when an accumulator instruction is executed. ZF is the zero flag and is set when the instruction causes the accumulator value to become zero. CF is the carry flag and is set when the instruction causes a carry. A carry is generated by addition, subtraction, multiplication, multiply-accumulate, compare, shifting and some MOV instructions (that have accumulation features). CF is reset if no carry occurs after execution of an instruction. OF is set when a computation causes overflow in the result. It is reset if no overflow occurs during an accumulator based instruction. Overflow saturation mode is set by the OM bit as explained in section 4.6.

4-6

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Texas Instruments MSP50C614 manual String Register STR, Status Register Stat

MSP50C614 specifications

The Texas Instruments MSP50C614 is a microcontroller that belongs to the MSP430 family, renowned for its low power consumption and versatile functionality. Primarily designed for embedded applications, this microcontroller is favored in various industries, including consumer electronics, industrial automation, and healthcare devices.

One of the standout features of the MSP50C614 is its ultra-low power technology, which enables it to operate in various power modes. This makes it ideal for battery-powered applications, where energy efficiency is crucial. The MSP430 architecture allows for a flexible power management system, ensuring that energy is conserved while providing robust performance.

The MSP50C614 is equipped with a 16-bit RISC CPU that delivers high performance while maintaining low power usage. With a maximum clock frequency of 16 MHz, it can execute most instructions in a single cycle, resulting in swift operation and responsive performance. This microcontroller also comes with a generous flash memory capacity, allowing developers to store large amounts of code and data conveniently.

In terms of peripherals, the MSP50C614 is highly versatile. It features a range of digital and analog input/output options, including multiple timers, GPIO ports, and various communication interfaces like UART, SPI, and I2C. This extensive set of peripherals allows for seamless integration with other components and simplifies the design of complex systems.

The integrated 12-bit Analog-to-Digital Converter (ADC) stands out as a valuable characteristic of the MSP50C614. This feature enables the microcontroller to convert physical analog signals into digital data, making it particularly useful for sensing applications and real-time monitoring.

Another noteworthy technology employed in the MSP50C614 is its support for low-voltage operations. With a broad supply voltage range, this microcontroller can function efficiently in diverse environments and is suitable for low-power applications, enhancing its practicality.

Moreover, Texas Instruments provides software support in the form of Code Composer Studio and various libraries that make it easier for developers to program and utilize the MSP50C614 effectively.

In summary, the Texas Instruments MSP50C614 microcontroller is a powerful, low-power solution equipped with the features and technologies necessary for efficient operation in a wide array of applications. Its blend of performance, flexibility, and energy efficiency makes it a popular choice among engineers and designers looking to create innovative, sustainable designs in the rapidly evolving tech landscape.