29-09-2012, 05:20 PM
Designing Low Power Products Using MSP430 Microcontroller
Designing Low Power.docx (Size: 404.97 KB / Downloads: 35)
The use of battery-operated electronics gadgets is increasing fast in our daily lives. Products are expected to be versatile, while consuming minimal power. Reduced power consumption has added advantages of smaller size and cost-effective products.
The MSP430 family of ultra-low power microcontrollers from Texas Instruments meets these requirements well. These microcontrollers combine a number of precision components like comparators and analogue-to-digital converters with the versatility of a 16-bit CPU, Flash memory and many digital modules. The entire architecture is aimed at operating the end product at the lowest power without compromising on accuracy and functionality. Its low cost is an additional attribute that has seen the use of MSP430 microcontroller in products like blood-glucose meters, energy meters, clinical thermometers, handheld weather monitors and handheld precision instruments.
Software program
The Blinking_LED.c program is written in 'C' language can be downloaded from the link at the end of the article. The program starts with the msp430×20×3.h header file for MSP30F2013 device. This file is automatically picked up by the compiler from the IAR installation directory during program compilation. At the beginning of the program, the watchdog timer needs to be stopped. Otherwise, it will cause a non-maskable interrupt after about 32 ms.
Now, set up the clock system. By default, MCLK and SMCLK start off with the internal digitally controlled oscillator (DCO) at 1 MHz.ACLK has been programmed to use the internal very low-frequency oscillator (VLO), whose oscillation frequency is approximately 10 kHz. So there is no need to connect any external crystal.
Next, configure the port modules. The unused bits of port 1 are programmed as outputs with a value of zero. This ensures that stray voltages on this port don’t cause in advertent leakage currents. Port 2.6 is configured as the output to drive the LED through resistor R29.