Division, Function Calls | Texas Instruments MSP50C614 manual

Implementation Details

5.10.2 Division

The integer division currently requires the use of several accumulator pointers. We divide a 16 bit integer located in A0 by a 16 bit integer located in A0~. We return the quotient in A0~, and the remainder in A0. We make use of A3~ and A3 for scratch pads. We also set flag 1 if a division by zero is attempted, and zero out the quotient and the remainder in this case. We also use PH for temporary storage of the divisor.

5.10.3 Function Calls

Every function is associated with a stack frame. A regular C program is initially given control by a call to main(). A C± ± program starts with a jump to the _main symbol, which must therefore be present in the C± ± source code.

The stack frame has the following structure:

First Argument

•••

Last Argument

Return Address

Previous BP

Locals

Low Address

⇓

High Address

BP is the frame pointer (base pointer), SP the stack pointer.

We use R7 for stack pointer, and yet another register for BP, REG_BP (R5, because of its special arithmetic capabilities). Before a function is called, the arguments are pushed on the stack, first argument first. The function call automatically pushes the return address on the stack. Immediately upon entering the function body, the current BP is pushed on the stack to preserve it, so that the stack pointer now points to the next location. This location is copied to REG_BP, which becomes our fixed reference point for the current function. Locals are then allocated on the stack from this starting location.

When the function returns, SP is made to point to the return address, after the previous BP is popped. The return is performed by a RET instruction. The calling routine is then responsible for moving the stack pointer to its previous location, before the arguments were put on the stack. Because all functions return via A0, the only function return type allowed is integer. Our implementation of C± ± allows for function prototyping, and checks that prototyped functions are called with the correct number of arguments.

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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.

Texas Instruments MSP50C614 Division, Function Calls, Stack frame has the following structure

Models: MSP50C614