Instruction Syntax and Addressing Modes

4.3.4Direct Addressing

Direct addressing always requires two instruction words. The second word operand is used directly as the memory address. The memory operand may be a label or an expression.

Syntax:

name [dest,] [src,] *dma16 [* 2] [, next A] name *dma16 [* 2] [, src] [, next A]

Memory Operand

Operand

Note the multiplication by 2 with the data memory address. This only needs to be done for word addresses, i.e., the address that points to 16-bit words. This is not required for byte addresses. This is explained in detail in section 4.5.

Example 4.3.5 MOV A2, *0x022A * 2

Refer to the initial processor state in Table 4±8 before execution of this instruc- tion. Loads the contents of data memory location 0x022A (=0x0400) to A2 or AC11. The MSP50P614/MSP50C614 always accesses data memory as byte addresses. To read a word address, multiply the address by 2. Final result, A2 = AC11 = 0x0400.

Example 4.3.6 MOV A1~, *0x01F2 * 2, ++A

Refer to the initial processor state in Table 4±8 before execution of this instruc- tion. Preincrement AP1. After preincrement A1 is AC22 and A1~ is AC6. The content of data memory location 0x01F2 (=0x12AC) is then loaded to accumu- lator AC22 (offset of AC6). Final result, AP1=22, AC6 = 0x12AC.

Example 4.3.7 SUB A1~, A1, *0x02A1 * 2, ±±A

Refer to the initial processor state in Table 4±8 before execution of this instruc- tion. Predecrement AP1. After predecrement A1 is AC20 and A1~ is AC4. Sub- tract the content of 0x02A1 (=0x1001) in data memory from AC20 and store result to AC4. Final result, AP1 = 20, AC4 = AC20 ± 0x1001 = 0x3321 ± 0x1001 = 0x2320.

Example 4.3.8

MOV *0x012F * 2, *A0

Refer to the initial processor state in Table 4±8 before execution of this instruc- tion. This is a table lookup instruction. This instruction reads the program memory address stored in A0 or AC2 and stores the data in data memory loca- tion 0x012F. Final result, *0x012F = 0x1B12.

Example 4.3.9

MULR *0x02A1 * 2

Refer to the initial processor state in Table 4±8 before execution of this instruc- tion. Multiply MR with the contents of 0x02A1. The MSB of the result is stored in PH register and rounded. The LSB is ignored. Final result, multiply MR • *0x02A1 = 0x1A15 •0x1001 = 0x1A16A15, PH = 0x01A1.

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Texas Instruments MSP50C614 manual Direct Addressing, MOV *0x012F * 2, *A0, Mulr *0x02A1
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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.
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