Thread: Introducing to MSP430

Key features of MSP430 microcontrol¬ler are:

1. 16-bit RISC CPU

2. Current drawn is less than O.I11A in 'off mode (RAM retention) and less than 0.5 llA in 'standby' mode

3. The microcontroller can wake up in less than 1 llS from power-down to full-speed functional mode

4. Zero-power-brownout detection circuit

5. 1kB to 128kB in-system-program¬mabie (ISP) Flash memory

6. Intelligent peripherals to boost performance and versatility. These include:

• Timers .ADC
• Comparators
• LCD drivers
• Communication ports like UART, SPI, FC and IrDA

7. Embedded emulation

8. 14-pin to 100-pin packing options

The microcontroller features multipIe frequency clocks so as to run peripherals at the required frequency. There are three clocks in total, of which ACLK (auxiliary clock) is the low-frequency clock while MCLK (main clock) is the master clock which is normally at a higher frequency (see Big. 1). The third is SMCLK (sub-main clock).

ACLK can be sourced from an ex¬ternal 32.768kHz watch crystal or an internal very low-frequency oscillator (VLO). The CPU is driven by MCLK, which is derived from the internal high-frequency digitally controlled oscillator (DCO) whose frequency can be selected using software setting. MSP430 is designed to extensively support interrupt-driven burst processing as indicated in Figs 1 and 2. This ensures ultra-low-power operation of the system.

Key features of its 16-bit CPU are:

1. No accumulator bottleneck
2. RISC architecture with:

• 27 core instructions
• 24 emulated instructions
• 7 addressing modes
• Constant generator

3. Single-cycle register operations

4. Memory-to-memory atomic addressing

5. Bit, byte and word processing In this part of the article, we have described the Flash programmercum-emulator for MSP430 family devices that can be built with readily available components. Part 2 of the article will demonstrate two examples: a blinking LED circuit and a circuit to read temperature accu¬rately on a digital multimeter based on MSP430F2013 chip. The pin details of a 14-pin MSP430F2013 device are shown in.

MSP430F2013 features a 16MHz CPU, 2kB Flash and 128-byte RAM. It has a 16-bit sigma-delta ADC, about ten ports with interrupt capability and in-built pull-up/ pull-down resistors, 16-bit versatile timer with two outputs, 16-bit watchdog timer, SPI and FC interfaces, and a zero-power-brownout