TI MSP430

There are, however, limits that preclude its use in more complex embedded systems. The MSP430 does not have an external memory bus, so it is limited to on-chip memory, up to 512 KB flash memory and 66 KB random-access memory (RAM), which may be too small for applications needing large buffers or data tables. Also, although it has a DMA controller, it is very difficult to use it to move data off the chip due to a lack of a DMA output strobe.[4]

The MSP430x1xx Series is the basic generation without an embedded LCD controller. They are generally smaller than the '3xx generation. These flash- or ROM-based ultra-low-power MCUs offer 8 MIPS, 1.8–3.6 V operation, up to 60 KB flash, and a wide range of analog and digital peripherals.

• Power specification overview, as low as:
  • 0.1 μA RAM retention
  • 0.7 μA real-time clock mode
  • 200 μA / MIPS active
  • Features fast wake-up from standby mode in less than 6 µs.

• Device parameters
  • Flash options: 1–60 KB
  • ROM options: 1–16 KB
  • RAM: 128 B–10 KB
  • GPIO options: 14, 22, 48 pins
  • ADC options: Slope, 10 & 12-bit SAR
  • Other integrated peripherals: 12-bit DAC, up to 2 16-bit timers, watchdog timer, brown-out reset, SVS, USART module (UART, SPI), DMA, 16×16 multiplier, Comparator_A, temperature sensor

The MSP430F2xx Series are similar to the '1xx generation, but operate at even lower power, support up to 16 MHz operation, and have a more accurate (±2%) on-chip clock that makes it easier to operate without an external crystal. These flash-based ultra-low power devices offer 1.8–3.6 V operation. Includes the very-low power oscillator (VLO), internal pull-up/pull-down resistors, and low-pin count options.

• Power specification overview, as low as:
  • 0.1 μA RAM retention
  • 0.3 μA standby mode (VLO)
  • 0.7 μA real-time clock mode
  • 220 μA / MIPS active
  • Feature ultra-fast wake-up from standby mode in less than 1 μs

• Device parameters
  • Flash options: 1–120 KB
  • RAM options: 128 B – 8 KB
  • GPIO options: 10, 11, 16, 24, 32, and 48 pins
  • ADC options: Slope, 10 & 12-bit SAR, 16 & 24-bit Sigma Delta
  • Other integrated peripherals: operational amplifiers, 12-bit DAC, up to 2 16-bit timers, watchdog timer, brown-out reset, SVS, USI module (I²C, SPI), USCI module, DMA, 16×16 multiplier, Comparator_A+, temperature sensor

The MSP430G2xx Value Series features flash-based Ultra-Low Power MCUs up to 16 MIPS with 1.8–3.6 V operation. Includes the Very-Low power Oscillator (VLO), internal pull-up/pull-down resistors, and low-pin count options, at lower prices than the MSP430F2xx series.

• Ultra-Low Power, as low as (@2.2 V):
  • 0.1 μA RAM retention
  • 0.4 μA Standby mode (VLO)
  • 0.7 μA real-time clock mode
  • 220 μA / MIPS active
  • Ultra-Fast Wake-Up From Standby Mode in <1 μs

• Device parameters
  • Flash options: 0.5–56 KB
  • RAM options: 128 B–4 KB
  • GPIO options: 10, 16, 24, 32 pins
  • ADC options: Slope, 10-bit SAR
  • Other integrated peripherals: Capacitive Touch I/O, up to 3 16-bit timers, watchdog timer, brown-out reset, USI module (I²C, SPI), USCI module, Comparator_A+, Temp sensor

The MSP430x3xx Series is the oldest generation, designed for portable instrumentation with an embedded LCD controller. This also includes a frequency-locked loop oscillator that can automatically synchronize to a low-speed (32 kHz) crystal. This generation does not support EEPROM memory, only mask ROM and UV-eraseable and one-time programmable EPROM. Later generations provide only flash memory and mask ROM options. These devices offer 2.5–5.5 V operation, up to 32 KB ROM.

• Power specification overview, as low as:
  • 0.1 μA RAM retention
  • 0.9 μA real-time clock mode
  • 160 μA / MIPS active
  • Features fast wake-up from standby mode in less than 6 µs.

• Device parameters:
  • ROM options: 2–32 KB
  • RAM options: 512 B–1 KB
  • GPIO options: 14, 40 pins
  • ADC options: Slope, 14-bit SAR
  • Other integrated peripherals: LCD controller, multiplier

The MSP430x4xx Series are similar to the '3xx generation, but include an integrated LCD controller, and are larger and more capable. These flash or ROM based devices offers 8–16 MIPS at 1.8–3.6 V operation, with FLL, and SVS. Ideal for low power metering and medical applications.

• Power specification overview, as low as:
  • 0.1 μA RAM retention
  • 0.7 μA real-time clock mode
  • 200 μA / MIPS active
  • Features fast wake-up from standby mode in less than 6 µs.

• Device parameters:
  • Flash/ROM options: 4 – 120 KB
  • RAM options: 256 B – 8 KB
  • GPIO options: 14, 32, 48, 56, 68, 72, 80 pins
  • ADC options: Slope, 10 & 12-bit SAR, 16-bit Sigma Delta
  • Other integrated peripherals: SCAN_IF, ESP430, 12-bit DAC, Op Amps, RTC, up to 2 16-bit timers, watchdog timer, basic timer, brown-out reset, SVS, USART module (UART, SPI), USCI module, LCD Controller, DMA, 16×16 & 32x32 multiplier, Comparator_A, temperature sensor, 8 MIPS CPU Speed

The MSP430x5xx Series are able to run up to 25 MHz, have up to 512 KB flash memory and up to 66 KB RAM. This flash-based family features low active power consumption with up to 25 MIPS at 1.8–3.6 V operation (165 uA/MIPS). Includes an innovative power management module for optimal power consumption and integrated USB.[5]

• Power specification overview, as low as:
  • 0.1 μA RAM retention
  • 2.5 μA real-time clock mode
  • 165 μA / MIPS active
  • Features fast wake-up from standby mode in less than 5 µs.

• Device parameters:
  • Flash options: up to 512 KB
  • RAM options: up to 66 KB
  • ADC options: 10 & 12-bit SAR
  • GPIO options: 29, 31, 47, 48, 63, 67, 74, 87 pins
  • Other optional integrated peripherals: 12-bit DAC, High resolution PWM, 5 V I/O's, USB, backup battery switch, up to 4 16-bit timers, watchdog timer, Real-Time Clock, brown-out reset, SVS, USCI module, DMA, 32x32 multiplier, Comp B, temperature sensor

The MSP430x6xx Series are able to run up to 25 MHz, have up to 512 KB flash memory and up to 66 KB RAM. This flash-based family features low active power consumption with up to 25 MIPS at 1.8–3.6 V operation (165 uA/MIPS). Includes an innovative power management module for optimal power consumption and integrated USB.

• Power specification overview, as low as:
  • 0.1 μA RAM retention
  • 2.5 μA real-time clock mode
  • 165 μA / MIPS active
  • Features fast wake-up from standby mode in less than 5 µs.

• Device parameters:
  • Flash options: up to 512 KB
  • RAM options: up to 66 KB
  • ADC options: 12-bit SAR
  • GPIO options: 74 pins
  • Other integrated peripherals: USB, LCD, DAC, Comparator_B, DMA, 32x32 multiplier, power management module (BOR, SVS, SVM, LDO), watchdog timer, RTC, Temp sensor

The RF SoC (CC430) Series provides tight integration between the microcontroller core, peripherals, software, and RF transceiver. Features <1 GHz RF transceiver, with 1.8 V–3.6 V operation. Programming using Arduino integrated development environment (IDE) is possible via the panStamp API.

• Power specification overview, as low as:
  • 1 μA RAM retention
  • 1.7 μA real-time clock mode
  • 180 μA / MIPS active

• Device parameters:
  • Speed options: up to 20 MHz
  • Flash options: up to 32 KB
  • RAM options: up to 4 KB
  • ADC options: 12-bit SAR
  • GPIO options: 30 & 44 pins
  • Other integrated peripherals: LCD Controller, up to 2 16-bit timers, watchdog timer, RTC, power management module (BOR, SVS, SVM, LDO), USCI module, DMA, 32x32 multiplier, Comp B, temperature sensor

The FRAM Series from Texas Instruments provides unified memory with dynamic partitioning and memory access speeds 100 times faster than flash. FRAM is also capable of zero power state retention in all power modes, which means that writes are guaranteed, even in the event of a power loss. With a write endurance of over 100 trillion cycles, EEPROM is no longer required. Active power consumption at less than 100μA/MHz.

• Power specification overview, as low as:
  • 320 nA RAM retention
  • 0.35 μA real-time clock mode
  • 82 μA / MIPS active

• Device parameters:
  • Speed options: 8 to 24 MHz
  • FRAM options: 4 to 256 KB
  • RAM options: 0.5 to 8 KB
  • ADC options: 10 or 12-bit SAR
  • GPIO options: 17 to 83 GPIO pins
  • Other possible integrated peripherals: MPU, up to 6 16-bit timers, watchdog timer, RTC, power management module (BOR, SVS, SVM, LDO), USCI module, DMA, multiplier, Comp B, temperature sensor, LCD driver, I2C and UART BSL, Extended Scan Interface, 32 bit multiplier, AES, CRC, signal processing acceleration, capacitive touch, IR modulation

The Low Voltage Series include the MSP430C09x and MSP430L092 parts, capable of running at 0.9 V. These 2 series of low voltage 16-bit microcontrollers have configurations with two 16-bit timers, an 8-bit analog-to-digital (A/D) converter, an 8-bit digital-to-analog (D/A) converter, and up to 11 I/O pins.

• Power specification overview, as low as:
  • 1 μA RAM retention
  • 1.7 μA real-time clock mode
  • 180 μA / MIPS active

• Device parameters:
  • Speed options: 4 MHz
  • ROM options: 1–2 kB
  • SRAM options: 2 kB
  • ADC options: 8-bit SAR
  • GPIO options: 11 pins
  • Other integrated peripherals: up to 2 16-bit timers, watchdog timer, brown-out reset, SVS, comparator, temperature sensor

More families within MSP430 include Fixed Function, Automotive, and Extended Temp parts.

Fixed Function: The MSP430BQ1010 16-bit microcontroller is an advanced fixed-function device that forms the control and communications unit on the receiver side for wireless power transfer in portable applications. MSP430BQ1010 complies with the Wireless Power Consortium (WPC) specification. For more information, see Contactless Power.

Automotive: Automotive MSP430 microcontrollers (MCUs) from Texas Instruments (TI) are 16-bit, RISC-based, mixed-signal processors that are AEC-Q100 qualified and suitable for automotive applications in environments up to 105 °C ambient temperature. LIN compliant drivers for the MSP430 MCU provided by IHR GmbH.

Extended Temp: MSP430 devices are very popular in harsh environments such as industrial sensing for their low power consumption and innovative analog integration. Some harsh environment applications include transportation/automotive, renewable energy, military/space/avionics, mineral exploration, industrial, and safety & security.

• Device Definitions:
  • HT: -55 °C to 150 °C
  • EP: Enhanced products -55 °C to 125 °C
  • Q1: Automotive Q100 qualified -40 °C to 105 °C
  • T: Extended temperature -40 °C to 105 °C applications

Note that when the flash size is over 64K words (128 KBytes), instruction addresses can no longer be encoded in just two bytes. This change in pointer size causes some incompatibilities with previous parts.

If the peripheral is not needed, the pin may be used for general purpose I/O. The pins are divided into 8-bit groups called "ports", each of which is controlled by a number of 8-bit registers. In some cases, the ports are arranged in pairs which can be accessed as 16-bit registers.

The MSP430 family defines 11 I/O ports, P0 through P10, although no chip implements more than 10 of them. P0 is only implemented on the '3xx family. P7 through P10 are only implemented on the largest members (and highest pin count versions) of the '4xx and '2xx families. The newest '5xx and '6xx families has P1 through P11, and the control registers are reassigned to provide more port pairs. Each port is controlled by the following registers. Ports which do not implement particular features (such as interrupt on state change) do not implement the corresponding registers.

PxIN

Port x input. This is a read-only register, and reflects the current state of the port's pins.

PxOUT

Port x output. The values written to this read/write register are driven out the corresponding pins when they are configured to output.

PxDIR

Port x data direction. Bits written as 1 configure the corresponding pin for output. Bits written as 0 configure the pin for input.

PxSEL

Port x function select. Bits written as 1 configure the corresponding pin for use by the specialized peripheral. Bits written as 0 configure the pin for general purpose I/O. Port 0 ('3xx parts only) is not multiplexed with other peripherals and does not have a P0SEL register.

PxREN

Port x resistor enable ('2xx & '5xx only). Bits set in this register enable weak pull-up or pull-down resistors on the corresponding I/O pins even when they are configured as inputs. The direction of the pull is set by the bit written to the PxOUT register.

PxDS

Port x drive strength ('5xx only). Bits set in this register enable high current outputs. This increases output power, but may cause electromagnetic interference (EMI).

Ports 0–2 can produce interrupts when inputs change. Further registers configure this ability:

PxIES

Port x interrupt edge select. Selects the edge which will cause the PxIFG bit to be set. When the input bit changes from matching the PxIES state to not matching it (i.e. whenever a bit in PxIES XOR PxIN changes from clear to set), the corresponding PxIFG bit is set.

PxIE

Port x interrupt enable. When this bit and the corresponding PxIFG bit are both set, an interrupt is generated.

PxIFG

Port x interrupt flag. Set whenever the corresponding pin makes the state change requested by PxIES. Can be cleared only by software. (Can also be set by software.)

PxIV

Port x interrupt vector ('5xx only). This 16-bit register is a priority encoder which can be used to handle pin-change interrupts. If n is the lowest-numbered interrupt bit which is pending in PxIFG and enabled in PxIE, this register reads as 2n+2. If there is no such bit, it reads as 0. The scale factor of 2 allows direct use as an offset into a branch table. Reading this register also clears the reported PxIFG flag.

Some pins have special purposes either as inputs or outputs. (For example, timer pins can be configured as capture inputs or PWM outputs.) In this case, the PxDIR bit controls which of the two functions the pin performs when the PxSEL bit is set. If there is only one special function, then PxDIR is generally ignored. The PxIN register is still readable if the PxSEL bit is set, but interrupt generation is disabled. If PxSEL is clear, the special function's input is frozen and disconnected from the external pin. Also, configuring a pin for general purpose output does not disable interrupt generation.

Analog

• Analog-to-digital converter

The MSP430 line offers two types of analog-to-digital conversion (ADC). 10- and 12-bit successive approximation converters, as well as a 16-bit sigma-delta converter. Data transfer controllers and a 16-word conversion-and-control buffer allow the MSP430 to convert and store samples without CPU intervention, minimizing power consumption.

• Analog pool

The Analog Pool (A-POOL) module can be configured as an ADC, DAC, comparator, SVS or temperature sensor. It allows flexibility for the user to program a series of analog functions with only one setup.

• Comparator A, A+

The MSP430's comparator module provides precision slope analog-to-digital conversions. Monitors external analog signals and provides voltage and resistor value measurement. Capable of selectable power modes.

• DAC12

The DAC12 module is a 12-bit, voltage-output DAC featuring internal/external reference selection and programmable settling time for optimal power consumption. It can be configured in 8- or 12-bit mode. When multiple DAC12 modules are present, they may be grouped together for synchronous update operation.

• Op Amps

Feature single supply, low current operation with rail-to-rail outputs and programmable settling times. Software selectable configuration options: unity gain mode, comparator mode, inverting PGA, non-inverting PGA, differential and instrumentation amplifier.

• Sigma Delta (SD)

The SD16/SD16_A/SD24_A modules each feature 16-/24-bit sigma-delta A/D converters with an internal 1.2-V reference. Each converter has up to eight fully differential multiplexed inputs, including a built-in temperature sensor. The converters are second-order oversampling sigma-delta modulators with selectable oversampling ratios of up to 1024 (SD16_A/SD24_A) or 256 (SD16).

Timers

• Basic timer (BT)

The BT has two independent 8-bit timers that can be cascaded to form a 16-bit timer/counter. Both timers can be read and written by software. The BT is extended to provide an integrated RTC. An internal calendar compensates for months with less than 31 days and includes leap-year correction.

• Real-Time Clock

RTC_A/B are 32-bit hardware counter modules that provide clock counters with a calendar, a flexible programmable alarm, and calibration. The RTC_B includes a switchable battery backup system that provides the ability for the RTC to operate when the primary supply fails.

• 16-bit timers

Timer_A, Timer_B and Timer_D are asynchronous 16-bit timers/counters with up to seven capture/compare registers and various operating modes. The timers support multiple capture/compares, PWM outputs, and interval timing. They also have extensive interrupt capabilities. Timer_B introduces added features such as programmable timer lengths (8-, 10-, 12-, or 16-bit) and double-buffered compare register updates, while Timer_D introduces a high-resolution (4 ns) mode.

• Watchdog (WDT+)

The WDT+ performs a controlled system restart after a software problem occurs. If the selected time interval expires, a system reset is generated. If the watchdog function is not needed in an application, the module can be configured as an interval timer and can generate interrupts at selected time intervals.

System

• Advanced Encryption Standard (AES)

The AES accelerator module performs encryption and decryption of 128-bit data with 128-bit keys according to the advanced encryption standard in hardware, and can be configured with user software.

• Brown-Out Reset (BOR)

The BOR circuit detects low supply voltages and resets the device by triggering a power-on reset (POR) signal when power is applied or removed. The MSP430 MCU’s zero-power BOR circuit is continuously turned on, including in all low-power modes.

• Direct Memory Access (DMA) Controller

The DMA controller transfers data from one address to another across the entire address range without CPU intervention. The DMA increases the throughput of peripheral modules and reduces system power consumption. The module features up to three independent transfer channels.

Although the MSP430's DMA subsystem is very capable it has several flaws, the most significant of which is the lack of an external transfer strobe. Although a DMA transfer can be triggered externally, there is no external indication of completion of a transfer. Consequently DMA to and from external sources is limited to external trigger per byte transfers, rather than full blocks automatically via DMA. This can lead to significant complexity (as in requiring extensive hand tweaking of code) when implementing processor to processor or processor to USB communications.[4] The reference cited uses an obscure timer mode to generate high speed strobes for DMA transfers. The timers are not flexible enough to easily make up for the lack of an external DMA transfer strobe.

DMA operations that involve word transfers to byte locations cause truncation to 8 bits rather than conversion to two byte transfers. This makes DMA with A/D or D/A 16 bit values less useful than it could be (although it is possible to DMA these values through port A or B on some versions of the MSP 430 using an externally visible trigger per transfer such as a timer output).

• Enhanced Emulation Module (EEM)

The EEM provides different levels of debug features such as 2-8 hardware breakpoints, complex breakpoints, break when read/write occurs at specified address, and more. Embedded into all flash-based MSP430 devices.

• Hardware multiplier

Some MSP430 models include a memory-mapped hardware multiplier peripheral which performs various 16×16+32→33-bit multiply-accumulate operations. Unusually for the MSP430, this peripheral does include an implicit 2-bit write-only register, which makes it effectively impossible to context switch. This peripheral does not interfere with CPU activities and can be accessed by the DMA. The MPY on all MSP430F5xx and some MSP430F4xx devices feature up to 32-bit x 32-bit.

The 8 registers used are:

Address	Name	Function
0x130	MPY	Operand1 for unsigned multiply
0x132	MPYS	Operand1 for signed multiply
0x134	MAC	Operand1 for unsigned multiply-accumulate
0x136	MACS	Operand1 for signed multiply-accumulate
0x138	OP2	Second operand for multiply operation
0x13A	ResLo	Low word of multiply result
0x13C	ResHi	High word of multiply result
0x13E	SumExt	Carry out of multiply-accumulate

The first operand is written to one of four 16-bit registers. The address written determines the operation performed. While the value written can be read back from any of the registers, the register number written to cannot be recovered.

If a multiply-accumulate operation is desired, the ResLo and ResHi registers must also be initialized.

Then, each time a write is performed to the OP2 register, a multiply is performed and the result stored or added to the result registers. The SumExt register is a read-only register that contains the carry out of the addition (0 or 1) in case of an unsigned multiply), or the sign extension of the 32-bit sum (0 or -1) in case of a signed multiply. In the case of a signed multiply-accumulate, the SumExt value must be combined with the most significant bit of the prior SumHi contents to determine the true carry out result (-1, 0, or +1).

The result is available after three clock cycles of delay, which is the time required to fetch a following instruction and a following index word. Thus, the delay is typically invisible. An explicit delay is only required if using an indirect addressing mode to fetch the result.

• Memory Protection Unit (MPU)

The FRAM MPU protects against accidental writes to designated read-only memory segments or execution of code from a constant memory. The MPU can set any portioning of memory with bit level addressing, making the complete memory accessible for read, write and execute operations in FRAM devices.

• Power management module (PMM)

The PMM generates a supply voltage for the core logic, and provides several mechanisms for the supervision and monitoring of both the voltage applied to the device and the voltage generated for the core. It is integrated with a low-dropout voltage regulator (LDO), brown-out reset (BOR), and a supply voltage supervisor and monitor.

• Supply-Voltage Supervisor (SVS)

The SVS is a configurable module used to monitor the AVCC supply voltage or an external voltage. The SVS can be configured to set a flag or generate a power-on reset (POR) when the supply voltage or external voltage drops below a user-selected threshold.

Communication and Interface

• Capacitive Touch Sense I/Os

The integrated capacitive touch sense I/O module offers several benefits to touch button and touch slider applications. The system does not require external components to create the self-oscillation (reducing bill of materials) and the capacitor (that defines the frequency of the self-oscillation) can be connected directly. In addition, there is no need for external MUXes to allow multiple pads and each I/O pad can directly serve as a cap sense input. A hysteresis of ~0.7 V ensures robust operation. Control and sequencing is done completely in software.

• General Purpose I/Os

MSP430 devices have up to 12 digital I/O ports implemented. Each port has eight I/O pins. Every I/O pin can be configured as either input or output, and can be individually read or written to. Ports P1 and P2 have interrupt capability. MSP430F2xx, F5xx and some F4xx devices feature built-in, individually configurable pull-up or pull-down resistors.

• Sub-GHz RF Front End

The flexible CC1101 sub-1 GHz transceiver delivers the sensitivity and blocking performance required to achieve successful communication links in any RF environment. It also features low current consumption and supports flexible data rates and modulation formats.

• USART (UART, SPI, I²C)

The universal synchronous/asynchronous receive/transmit (USART) peripheral interface supports asynchronous RS-232 and synchronous SPI communication with one hardware module. The MSP430F15x/16x USART modules also support I²C, programmable baud rate, and independent interrupt capability for receive and transmit.

• USB

The USB module is fully compliant with the USB 2.0 specification and supports control, interrupt and bulk transfers at a data rate of 12 Mbps (full speed). The module supports USB suspend, resume and remote wake-up operations and can be configured for up to eight input and eight output endpoints. The module includes an integrated physical interface (PHY); a phase-locked loop (PLL) for USB clock generation; and a flexible power-supply system enabling bus-powered and self-powered devices.

• USCI (UART, SPI, I²C, LIN, IrDA)

The universal serial communication interface (USCI) module features two independent channels that can be used simultaneously. The asynchronous channel (USCI_A) supports UART mode; SPI mode; pulse shaping for IrDA; and automatic baud-rate detection for LIN communications. The synchronous channel (USCI_B) supports I²C and SPI modes.

• USI (SPI, I²C)

The universal serial interface (USI) module is a synchronous serial communication interface with a data length of up to 16-bits and can support SPI and I²C communication with minimal software.

• Infrared Modulation

Available on the MSP430FR4xxx and MSP430FR2xxx series chips, this feature is configured via the SYSCFG register set. This peripheral ties into other peripherals (Timers, eUSCI_A) to generate an IR modulated signal on an output pin.[6] (page 43)

Metering

• ESP430 (integrated in FE42xx devices)

The ESP430CE module performs metering calculations independent of the CPU. Module has separate SD16, HW multiplier, and the ESP430 embedded processor engine for single-phase energy-metering applications.

• Scan Interface (SIF)

The SIF module, a programmable state machine with an analog front end, is used to automatically measure linear or rotational motion with the lowest possible power consumption. The module features support for different types of LC and resistive sensors and for quadrature encoding.

Display

• LCD/LCD_A/LCD_B

The LCD/LCD_A controller directly drives LCDs for up to 196 segments. Supports static, 2-mux, 3-mux, and 4-mux LCDs. LCD_A module has integrated charge pump for contrast control. LCD_B enables blinking of individual segments with separate blinking memory.

• LCD_E

The LCD_E controller comes with the newer MSP430FR4xxx series microcontrollers and directly drives LCDs up to 448 segments. Supports static, 2-mux, 3-mux, 4-mux, 5-mux, 6-mux, 7-mux, 8-mux (1/3 bias) LCDs. Segment and Common pins may be reprogrammed to available LCD drive pins. This peripheral may be driven in LPM3.5 (RTC running+Main CPU core shutdown low-power mode).[6]

TI has tackled the low-budget problem by offering a very small experimenter board, the eZ430-F2013, on a USB stick (now obsolete). This made it easy for designers to choose the MSP430 chip for inexpensive development platforms that can be used with a computer. The eZ430-F2013 contains an MSP430F2013 microcontroller on a detachable prototyping board, and accompanying CD with development software. It is helpful for schools, hobbyists and garage inventors. It is also welcomed by engineers in large companies prototyping projects with capital budget problems.

Texas Instruments released the MSP430 LaunchPad in July 2010. The MSP430 LaunchPad has an onboard flash emulator, USB, 2 programmable LEDs, and 1 programmable push button.[10] As an addition to experimentation with the LaunchPad a shield board is available.

TI has since provided several new LaunchPads based on the MSP430 platform:

• MSP-EXP430F5529LP features the MSP430F5529 USB device-capable MCU with 128KB flash and 8KB SRAM
• MSP-EXP430FR5969 features the MSP430FR5969 FRAM MCU with 64KB FRAM and 2KB SRAM
• MSP-EXP430FR4133 features the MSP430FR4133 FRAM MCU with 16KB FRAM, 2KB SRAM and on-board LCD
• MSP-EXP430FR6989 features the MSP430FR6989 FRAM MCU with 128KB FRAM, 2KB SRAM, on-board LCD and Extended Scan Interface peripheral
• MSP-EXP430FR2311 features the MSP430FR2311 FRAM MCU with 4KB FRAM, 1KB SRAM, OpAmp and Transimpedance Amplifier peripheral
• MSP-EXP430FR2433 features the MSP430FR2433 FRAM MCU with 15.5KB FRAM, 4KB SRAM
• MSP-EXP430FR2355 features the MSP430FR2355 FRAM MCU with 32KB FRAM, 4KB SRAM, 12-bit ADC, 12-bit DAC, OpAmp/PGA, ICC for nested interrupts
• MSP-EXP430FR5994 features the MSP430FR5994 FRAM MCU with 256KB FRAM, 8KB SRAM, 12-bit ADC and LEA DSP peripheral

All three of these LaunchPads include an eZ-FET JTAG debugger with backchannel UART capable of 1Mbit/s speeds. The FRAM LaunchPads (e.g. MSP-EXP430FR5969, MSP-EXP430FR4133) include EnergyTrace, a feature supported by TI's Code Composer Studio IDE for monitoring and analyzing power consumption.

Many added instructions are implemented as aliases for forms of the above. For example, there is no specific "return from subroutine" instruction, but it is implemented as "MOV @SP+,PC". Emulated instructions are:

Note that the immediate constants −1 (0xffff), 0, 1, 2, 4 and 8 can be specified in a single-word instruction without needing a separate immediate operand.

The basic MSP430 cannot support more memory (ROM + RAM + peripherals) than its 64K address space. In order to support this, an extended form of the MSP430 uses 20-bit registers and a 20-bit address space, allowing up to 1 MB of memory. This uses the same instruction set as the basic form, but with two extensions:

1. A limited number of 20-bit instructions for common operations, and
2. A general prefix-word mechanism that can extend any instruction to 20 bits.

The extended instructions include some added abilities, notably multibit shifts and multiregister load/store operations.

20-bit operations use the length suffix "A" (for address) instead of .B or .W. .W is still the default. In general, shorter operations clear the high-order bits of the destination register.

The new instructions are as follows:

All other instructions can have a prefix word added which extends them to 20 bits. The prefix word contains an added operand size bit, which is combined with the existing B/W bit to specify the operand size. One unused size combination exists; indications suggest that it may be used in future for a 32-bit operand size.[12]

The prefix word comes in two formats, and the choice between them depends on the instruction which follows. If the instruction has any non-register operands, then the simple form is used, which provides 2 4-bit fields to extend any offset or immediate constant in the instruction stream to 20 bits.

If the instruction is register-to-register, a different extension word is used. This includes a "ZC" flag which suppresses carry-in (useful for instructions like DADD which always use the carry bit), and a repeat count. A 4-bit field in the extension word encodes either a repeat count (0–15 repetitions in addition to the initial execution), or a register number which contains a 4-bit repeat count.

• TI MSP430 Homepage
• MSP430 TITAN Development Board
• TI E2E MSP430 Community forum
• MSP430 Community sponsored by Texas Instruments
• MSP430 Yahoo!group
• MSP430.info
• MSP430 English-Japanese forum
• 43oh.com – MSP430 News, Projects and Forums
• TinyOS-MSP430 – TinyOS port
• MSP430 Egel project pages – About 50 examples with sources, schematics, well documented.

• VisSim MSP430 Model-Based Embedded Development System

• Arduino IDE Arduino IDE
• Code Composer Studio Eclipse based IDE
• Code Composer Studio Cloud
• IAR Embedded Workbench Kickstart IDE (size limited to 4/8/16 KB – depends on device used)
• GCC toolchain for the MSP430 Microcontrollers
• MSP430 Development System
• naken_asm Open-Source MSP430 assembler, disassembler, simulator.
• Pre-built MSP430 GCC 4.x binaries for Windows
• MSP430 16-bit noForth compiler With assembler, disassembler and sources.
• FastForth with 5 MBds terminal, assembler, SD_Card driver...

• IAR Embedded Workbench for TI MSP430
• Rowley CrossWorks for MSP430 (only a 30-day evaluation period)
• GCC toolchain for the MSP430 Microcontrollers (Free C-compiler)
• MSP430 Development System
• A plugin for Visual Studio that supports MSP430 via MSP430-GCC (30-day evaluation)

• AQ430 Development Tools for MSP430 Microcontrollers
• ImageCraft C Tools
• ForthInc Forth-Compiler
• MPE Forth IDE & Cross-Compiler for MSP430 currently in Beta
• HI-TECH C for MSP430 (Dropped MSP430 Support in 2009)

• WSim – a software-driven emulator for full platform estimations and debug
• MSPSim – a Java based MSP430 emulator/simulator
• MSP430Static – a reverse engineering tool in Perl
• GoodFET – an open MSP430 JTAG debugger in C and Python
• mspdebug – an opensource MSP430 JTAG debugger
• Trace32 MSP430 SIM – Download area with MSP430 Instruction Set Simulator free for evaluation
• ERIKA Enterprise – a free of charge, open source RTOS implementation of the ISO 17356 API (derived from the OSEK/VDX API)
• Energia is based on Wiring and Arduino and uses the Processing IDE. The hardware platform is based upon TI MSP430 LaunchPad