msp430 lcd display code brands

This article is the continuation of our tutorial series on programming MSP430 using Code Composer Studio. Last tutorial was based on GPIO pins. This tutorial is about interfacing a display with MSP430, when it comes to display the 16*2 LCD Display,it is the first choice for any electronic hobbyist. Previously we have also interfaced LCD with MSP430 using Arduino IDE, in this tutorial, we will use the native Code Composer studio platform instead of using the Arduino IDE, this way as a designer, we get more flexibility.

It has an in-built IC hd44780 that can store the command and data passed to it. The LCD Module has about 16 pins. 8 of which are data pins, 4 of them are supply pins for backlight LED and the whole LCD module, 3 for controlling the operation, and 1 pin for contrast adjustment. The tutorial is based on the library created by Dennis Eichmann. It is very easy to use a library with separate functions to print different data types. It also has provisions to display the data in different forms with leading, blanked, and deleted zeroes. It is a pretty expansive and comprehensive library and is configurable to the different connections. Here, the header file is modified to accommodate an 8-pin parallel configuration for data communication.

A generic 16x2 Display has an inbuilt hd44780 IC(circled in red below), that can store the command and data passed to it. The LCD Module has about 16 pins. 8 of which are data pins, 4 of them are supply pins for backlight LED and the whole LCD module, 3 for controlling the operation, and 1 pin for contrast adjustment.

This LCD module is shown above versatile and uses minimum pins compared to other segmented LCDs. If you are curious to know how exactly all this works, you should check out the working of the 16x2 LCD display where we have already discussed how the LCD works in detail.

RS Pin: RS=1 will enable the data register in the LCD, which is used to write the values to the data register in LCD. RS=0 will enable the Instruction register of the LCD.

Enable pin: Negative edge-triggered; when the pin is changed from the HIGH state to LOW state, LCD is prompted to write to the data pins. Positive edge-triggered; when the pin is changed from the LOW state to HIGH state, LCD is prompted to read from the data pins.

The tutorial is based on the library created by Dennis Eichmann. It is very easy to use a library with separate functions to print different data types. It also has provisions to display the data in different forms with leading, blanked, and deleted zeroes. It is a pretty expansive and comprehensive library and is configurable to the different connections. Here, the header file is modified to accommodate an 8-pin parallel configuration for data communication. The library can be download from the below link, after downloading you follow the below steps to add the library to CCS.

In the properties dialog box of the hd44780 project and inside the include options for the MSP430 compiler, add the include folder in file the search path.

In the properties dialog box for the CCS_LCD project and in the file search path of MSP430 Linker tab, include the hd44780.lib located inside the debug folder of the hd44780 project. The debug folder is also included in the file search path.

void hd44780_timer_isr( void ):This is periodically called in the ISR of the Timer A. The Timer A is used to periodically do the LCD functions like clearing the screen, setting the cursor, and displaying the data. The function is to be used in the ISR. It returns nothing.

char * ch__string:The string to be written to the data buffer (inside the hd44780_timer_isrfunction). The data will be copied to the data register and instruction register of the LCD IC when the hd44780_timer_isris periodically called.

uint8_t hd44780_output_unsigned_16bit_value( uint16_t u16__value, uint8_t u8__leading_zero_handling, uint8_t u8__row, uint8_t u8__column, uint8_t u8__cr_lf ):The function will display the unsigned 16-bit value on the desired location of the LCD.

The anode of the LED backlight cannot be connected directly to a 5V supply. It should be connected to a resistance to minimize the current flow through the LCD Module. I have made my connections using a perf board to solder the LCD and then used jumper wires to connect the LCD with the MSP430 board, my set-up looks like this below but you can also simply use a breadboard to make your connections.

The complete code used in this project is given at the bottom of this page. The explanation of using the code is as follows. First, open the header file (hd44780.h) and include the microcontroller part number in the first part of the file.

Inbuilt timer is being used to display values periodically. Timer A is selected with SMCLK (1MHZ) as the clock source and continuous mode being the mode of operation.

Once you have your code compiled, you can upload it to the MSP430 board, as explained in the getting started with the MSP430 tutorial. If everything goes as expected, you should see your LCD display some contrast as shown below.

The LCD chosen was the: NHD-0216HZ-FSW-FBW-33V3C Character Liquid Crystal Display Module.  2 Lines x 16 Characters and it has a Built?in controller (ST7066U or equivalent)

In the datasheet I saw the 4 bit initialization pseudocode and I am working the project on assembly language on IAR, my question is how can I convert this code to assembly language so I can display something succesfully on the LCD display with the MSP430.

Alphanumerical LCDs are probably the easiest devices to quickly project information visually. They are easy to use and cheap. To be able to use them, we do not need any additional hardware feature of a micro or any special communication hardware like I2C and SPI. Digital I/Os are what we need to use these displays. Just like my other tutorials, this tutorial includes three LCD examples – one with software SPI communication, one with software I2C communication and one with direct DIO-based 4-bit LCD interface.

Be sure to use 3.3V compatible LCD because most of them don’t operate at 3.3V power level. Most of the LCD are designed for 5V operation. It is okay to use 5V power supply for powering LCD if there is no other option. LCDs accept 0V – 3.3V logic level. However, there should be no way with which a 5V power supply/device can get connected with MSP430’s 3.3V power bus.

Most popularly alphanumerical LCDs are driven in 4-bit data mode and this is what that has been done here. First let’s see some typical LCD instructions.

Since alphanumerical displays utilize GPIOs, there’s hardly anything to explain here. Try not to use GPIOs that have alternate roles because you may never know when would you need their alternative functions.

Most popularly alphanumerical LCDs are driven in 4-bit data mode and this is what that has been done here. First let’s see some typical LCD instructions.

I"m having trouble getting my msp430 to communicate with a 16x4 LCD screen. Data sheet for the LCD screen: https://www.beta-estore.com/download/rk/RK-10290_410.pdf

I"m pretty positive all my pins are connected correctly. The LCD is projecting light but that"s it. I can"t even get the cursor to show up and blink on the screen. I have my bus connected to 8 LED lights so I can be sure the correct commands are being sent. That is also why I have the long delay in between each write operation. Not sure what to do from here to troubleshoot. Any help would be greatly appreciated.

I had some parts lying around, and I wanted to give them some purpose. So I went ahead and pimped my breadboard with an i2c scanner. The scanner basically looks for the device"s slave address then displays it on the LCD screen. This makes it easier to find the address without diving into the datasheet. I still suggest CTRL+F the displayed slave address within the datasheet to confirm.

It"s important to test things out before soldering and mounting things together. So I started out by wiring connections to their respective ports (as seen on the schematics posted), then uploaded the code onto the MSP430 devboard using Energia (TI"s fork of the Arduino IDE).

Once it"s working properly, I did the following:I soldered my rendition of a MSP430 barebones board. It"s definitely missing some parts like decoupling capacitors and whatnot, but it works.

I encountered some problems where the was code working with the devboard but not with the barebones board. To fix it, I needed to modify theboards.txtfound inC:\Users\yourusername\AppData\Local\Energia15\packages\energia\hardware\msp430\1.0.3.The directory can be different in your system.

I don"t quite remember what I changed but here"s what I have for the M430G2553 inboards.txt:#MSP-EXP430G2553MSP-EXP430G2553LP.vid.0=0x2341MSP-EXP430G2553LP.pid.0=0x0c9fMSP-EXP430G2553LP.name=MSP-EXP430G2 w/ MSP430G2553MSP-EXP430G2553LP.build.mcu=msp430g2553MSP-EXP430G2553LP.build.f_cpu=16000000LMSP-EXP430G2553LP.build.core=msp430MSP-EXP430G2553LP.build.variant=MSP-EXP430G2553LPMSP-EXP430G2553LP.build.board=MSP_EXP430G2553LPMSP-EXP430G2553LP.build.extra_flags=MSP-EXP430G2553LP.upload.tool=mspdebugMSP-EXP430G2553LP.upload.protocol=rf2500MSP-EXP430G2553LP.upload.maximum_size=16384MSP-EXP430G2553LP.upload.maximum_data_size=512

Caveats: One thing I noticed is that the scanner returns a random HEX when the device is not hooked up properly.The same is true when nothing is plugged in.Thiscan be mitigated by adding more code to catch the error thendisplay thaterror message.

Photo of two experimenter boards for the MSP430 chipset by Texas Instruments. On the left the larger chip version, on the right a small version in USB format.

The MSP430 is a mixed-signal microcontroller family from Texas Instruments, first introduced on 14 February 1992.CPU, the MSP430 is designed for low cost and, specifically, low power consumption

The MSP430 can be used for low powered embedded devices. The current drawn in idle mode can be less than 1 µA. The top CPU speed is 25 MHz. It can be throttled back for lower power consumption. The MSP430 also uses six different low-power modes, which can disable unneeded clocks and CPU. Further, the MSP430 can wake-up in times under 1 microsecond, allowing the controller to stay in sleep mode longer, minimizing average current use.

Some less usual peripheral options include comparators (that can be used with the timers to do simple ADC), on-chip operational amplifiers (op-amp) for signal conditioning, 12-bit digital-to-analog converter (DAC), liquid crystal display (LCD) driver, hardware multiplier, USB, and direct memory access (DMA) for ADC results. Apart from some older erasable programmable read-only memory (EPROM, such as MSP430E3xx) and high volume mask ROM (MSP430Cxxx) versions, all of the devices are in-system programming enabled via Joint Test Action Group (JTAG), full four-wire or Spy-Bi-Wire), a built in bootstrapping loader (BSL) using UART such as RS-232, or USB on devices with USB support. No BSL is included in F20xx, G2xx0, G2xx1, G2xx2, or I20xx family devices.

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.

Six general generations of MSP430 processors exist. In order of development, they are: "3xx generation, "1xx generation, "4xx generation, "2xx generation, "5xx generation, and "6xx generation. The digit after the generation identifies the model (generally higher model numbers are larger and more capable), the third digit identifies the amount of memory included, and the fourth, if present, identifies a minor model variant. The most common variation is a different on-chip analog-to-digital converter.

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.

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.

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.

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.

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.

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.

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.

Other integrated peripherals: USB, LCD, DAC, Comparator_B, DMA, 32x32 multiplier, power management module (BOR, SVS, SVM, LDO), watchdog timer, RTC, Temp sensor

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

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.

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 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.

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.

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.

The MSP430 peripherals are generally easy to use, with (mostly) consistent addresses between models, and no write-only registers (except for the hardware multiplier).

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.

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.

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.

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.

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.

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.

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.

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 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.

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.

The universal synchronous/asychrnous 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.

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.

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.

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).

Texas Instruments provides various hardware experimenter boards that support large (approximately two centimeters square) and small (approximately one millimeter square) MSP430 chips. TI also provides software development tools, both directly, and in conjunction with partners (see the full list of compilers, assemblers, and IDEs). One such toolchain is the IAR C/C++ compiler and debugger (assembly language programs of any size can be developed and debugged with this free toolchain).

TI also combines a version of its own compiler and tools with its Eclipse-based Code Composer Studio IDE (CCS). It sells full-featured versions, and offers a free version for download which has a code size limit of 16 KB. CCS supports in-circuit emulators, and includes a simulator and other tools; it can also work with other processors sold by TI.

For those who are more comfortable with the Arduino, there is also another software Energia, an open source electronics prototyping platform with the goal to bring the Wiring and Arduino framework to the Texas Instruments MSP430 based LaunchPad where Arduino code can be exported for programming MSP430 chips. The latest release of Energia supports the MSP-EXP430G2xxx, MSP-EXP430FR5739, MSP-EXP430FR5969, MSP-EXP430FR5994, MSP-EXP430F5529LP, Stellaris EK-LM4F120XL, Tiva-C EK-TM4C123GXL, Tiva-C EK-TM4C1294XL, CC3200 WiFi LaunchPad.

TI consulted with RedHat to provide official support for the MSP430 architecture to the GNU Compiler Collection C/C++ compiler. This msp430-elf-gcc compiler is supported by TI"s Code Composer Studio version 6.0 and higher.

Other commercial development tool sets, which include editor, compiler, linker, assembler, debugger and in some cases code wizards, are available. VisSim, a block diagram language for model based development, generates efficient fixed point C-Code directly from the diagram.closed loop ADC+PWM based PID control on the F2013 compiles to less than 1 KB flash and 100 bytes RAM.

The MSP430F2013 and its siblings are set apart by the fact that (except for the MSP430G2 Value Line) it is the only MSP430 part that is available in a dual in-line package (DIP). Other variants in this family are only available in various surface-mount packages. TI has gone to some trouble to support the eZ430 development platform by making the raw chips easy for hobbyists to use in prototypes.

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

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.shield board is available.

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.

In common with other microcontroller vendors, TI has developed a two-wire debugging interface found on some of their MSP430 parts that can replace the larger JTAG interface. The eZ430 Development Tool contains a full USB-connected flash emulation tool (FET) for this new two-wire protocol, named

The advantage of the Spy-Bi-Wire protocol is that it uses only two communication lines, one of which is the dedicated _RESET line. The JTAG interface on the lower pin count MSP430 parts is multiplexed with general purpose I/O lines. This makes it relatively difficult to debug circuits built around the small, low-I/O-budget chips, since the full 4-pin JTAG hardware will conflict with anything else connected to those I/O lines. This problem is alleviated with the Spy-Bi-Wire-capable chips, which are still compatible with the normal JTAG interface for backwards compatibility with the old development tools.

JTAG debugging and flash programming tools based on OpenOCD and widely used in the ARM architecture community are not available for the MSP430. Programming tools specially designed for the MSP430 are marginally less expensive than JTAG interfaces that use OpenOCD. However, should it be discovered mid-project that more MIPS, more memory, and more I/O peripherals are needed, those tools will not transfer to a processor from another vendor.

The MSP430 CPU uses a von Neumann architecture, with a single address space for instructions and data. Memory is byte-addressed, and pairs of bytes are combined little-endian to make 16-bit words.

The MSP430X extension with 20-bit addressing adds added instructions that can require up to 10 clock cycles. Setting or clearing a peripheral bit takes two clocks. A jump, taken or not takes two clocks. With the 2xx series 2 MCLKs is 125 ns at 16 MHz.

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:

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.

There is a new extended version of the architecture (named MSP430X) which allows a 20-bit address space. It allows added program ROM beginning at 0x10000.

The size bit is named A/L, where L (long) is used by other processors to indicate 32-bit operands. Also the description of the SXTX instruction (MSP430F5xx Family User"s Guide alau208f page 237) describes the effect of the instruction in register bits 20–31.

In this MSP430 timer PWM tutorial the basic workings of the on board timer peripheral will be explained, along with some C code examples which can be downloadable at the end of the tutorial.  Additionally the video below demonstrates the examples ‘A picture paints a thousand words, a video displays a thousand pictures’.

The MSP430G2253 will be used as it has two timers opposed to the MSP430G2231 which only has one timer, this will allow for different examples to be shown.  All the code in the MSP430 timer tutorial is written in Code Composer Studio (CCS) v5.5.  As the tutorial will be using the MSP430G2253 as the test microcontroller, downloading the datasheet for this maybe of use and can be found here.

Before reading further if you are having trouble understanding how the registers work, and how the C code updates the individual register settings?  It would be worth reading my MSP430 Programming Tutorial, Part 1 covers the basics and Part 2 gives clear examples.  You can find them here Part 1 and Part 2.

The MSP430G2253 has two 16 bit timers, Timer0 and Timer1 both are Timer_A variants with three capture/compare registers.  The MSP430 family guide lists two types of 16 bit timer, Timer_A and Timer_B.  For the most part they are very similar except Timer_A has up to three capture/compare registers, were as Timer_B has up to seven.  The MSP430G2253 also has a watchdog timer which can be used detect system malfunctions, but will not be covered in this tutorial. The feature list for Timer_A is shown below:

The Timer_A capture/compare register 0 or TACCR0, is used in two cases.  In compare mode this holds the value for comparison with the timer value in the TAR.  When in capture mode, the value in the TAR is copied into the TACCR0 when a capture is performed.  An example of the register code would be as follows TA0CCR0 = 200-1;.

The Timer_A capture/compare control register 0 or TACCTL0, is a 16 bit register used to determine how the TACCR0 is set-up.  The register controls whether the timer module is set to capture or compare.  The trigger edge for the capture mode can be set, as well as where the source originates from, either internal or external.  Asynchronous or synchronous operation can determined, as well as synchronised capture or compare input.  There are various output modes, which are used to determine the operation of PWM signals for example.  Also this register allows interrupts to enabled for the timer module.  An example of the register code would be as follows TA0CCTL0 = OUTMOD_7 + CCIE;.

The Timer_A capture/compare register 1 or TACCR1.  Has the same operation as TACCR0.  An example of the register code would be as follows TA0CCR1 = 200-1;.

The Timer_A capture/compare control register 1 or TACCTL1, is a 16 bit register used to determine how the TACCR1 is set-up.  Has the same operation as TACCTL0.  An example of the register code would be as follows TA0CCTL1 = OUTMOD_7;.

The Timer_A capture/compare register 2 or TACCR2.  Has the same operation as TACCR0.  An example of the register code would be as follows TA0CCR2 = 200-1;.

The Timer_A capture/compare control register 2 or TACCTL2, is a 16 bit register used to determine how the TACCR2 is set-up.  Has the same operation as TACCTL0.  An example of the register code would be as follows TA0CCTL2 = CCIE;.

This first example demonstrates the use of one timer, which is used to flash the MSP430G2253 Launchpad LED’s on and off.  The code snippet below only shows the timer set-up and the interrupt handler, as these are the most relevant parts.

The code is fairly short and quite simple to walk through, in line 5 we first load the TA0CCR0 with the value 3000.  Line 6 turns the interrupt on for the TA0CCR0 when it overflows.  Line 7 sets the clock source to ACLK (12kHz) and the counter to count-up mode.  So the interrupt is generated every 250mS approximately.  Line 9 sets the MSP430 to low power mode and enables interrupts.  Lines 12 to 22 are the interrupt handler for Timer0_A, this interrupt automatically clears when called.  Inside the interrupt handler, the variable Control is used to ensure the green LED flashes once for every time the red LED flashes four times.  The closing brace marks the end of the main function.

The second example demonstrates the use of two timers, which are used to output PWM signals on GPIO pins P1.2 and P2.1.  The timer set-up code and also the GPIO set-up code is shown below.  The clock was set to 8MHz for this example.

Before walking through the code, the image below is extracted from the MSP430G2253 datasheet, this shows GPIO pin P1.2 and it’s functions.  The line which is highlighted demonstrates P1.2 can be used as an input and output for Timer0_A.

Walking through the code starting with line 5, this sets GPIO pin P1.2 as an output.  Line 6 selects the function for GPIO pin P1.2, and in this case it is used for PWM.  Lines 7 and 8 perform the same operation, except they are for GPIO pin P2.1.  line 11 the TA0CCR0 is loaded with 200, this sets the PWM frequency to 40kHz approximately.  Line 12 sets the output mode to reset/set.  Line 13 sets the count value of TA0CCR1, which determines the PWM duty cycle, in this case 50%. Line 14 sets the clock used by the TA0CTL to SMCLK and the counter to count-up mode.  Lines 17 to 20 set-up Timer1_A in the same way as Timer0_A, except the frequency is set to 8kHz approximately.

The third example demonstrates the use of two timers, using PWM generated by Timer0_A and a timed interrupt on Timer1_A to alter the duty cycle.  The PWM output is configured to output on GPIO pin P1.6.  As with the previous code examples, only the timer set-up code is shown. The clock was set to 1MHz for this example.

Lines 5 to 8 in this example are almost identical to lines 5 to 8 in the example 2 code.  The main difference is the PWM frequency is set to 1kHz (clock set to 1MHz) and the duty cycle is initially set to 0.1%.  Lines 11 to 13 set-up Timer1_A, this has a count of 4000 so generates an interrupt every 4mS.  Line 15 sets the MSP430 to low power mode and enables interrupts.

There is also one more additional example for the timer, which demonstrates the capture mode.  This is actually part of a another tutorial based around switch debouncing, the timer is used to capture the undesired pulses generated by a noisy switch.  You can find the additional code by browsing to the end of my Switch Debouncing Tutorial Pt/1.