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The key points from this module are:
An interrupt refers to the transfer of program control from a currently running program to another service program as a result of an external or internal generated request or event. It allows you to perform multiple tasks instead of polling.
There are three types of Interrupts in MSP430:

System Reset - It occurs due to supply voltage (VCC) and low signal in RST/NMI pin with Reset mode selected.
Non Maskable Interrupts - It is generated by sources like Oscillator faults and an edge manually given to the RST/NMI.
Maskable Interrupts - It occurs when an interrupt can be masked by a CPU instruction.

Another way to classify interrupts is vectored and non - vectored interrupts.

Vectored interrupts - When the interrupt occurs, the user knows exactly where to look for the subroutine to deal with the interrupt.
Non - Vectored interrupts - When the interrupt occurs, the system must provide some information to help locate the subroutine to handle the interrupt.

Interrupt has three registers namely Interrupt enable register (PxIE), Interrupt edge selection register (PxIES) and Interrupt flag register (PxIFG). All the registers are 8- bit registers.  
The following are Check Lists for interrupt to happen:

Enable interrupts both in their module and generally
Provide ISR for all the enabled interrupts
Include code to acknowledge interrupt that share a vector or even if only 1 source is active
Declare variables as volatile

The MSP430 was designed primarily for low power applications and this is reflected in a range of low-power modes of operation.
MSP430 has 6 operating modes, five of which are low power modes.:

Active mode - All clocks are active and supply current at 1MHz: 230uA(at 2.2V), 330uA(at 3.0V)
LPM0 - The CPU is disabled. No program is executing but some of the peripherals. Supply current(at 1MHz): 56uA(at 2.2V).

LPM1 - The CPU is disabled. A clock and SM clock are still active,  MKCL is also disabled.



LPM2 - The CPU is disabled. M clock and SM clock both are disabled, the DCO can be on, the DCO’s DC generator remains enabled. Supply current: 22uA(at 2.2V).




LPM3 - The CPU is disabled, M clock and S clock are also disabled, the DCO’s DC generator is disabled. Supply current: 0.5uA(at 2.2V).




LPM4 - The CPU is disabled, the A clock is also disabled, the rest of the clocks are also disabled, DCO generator is disabled, the crystal oscillator is stopped. Supply current: 0.1uA(at 2.2V).
 
There are four types of LCD displays, namely;
 


Numeric - This allows you to display information in seven segment format.
Alphanumeric - This allows you to display alphabetical characters with little more clarity than is possible with a numeric displays.
Character - This allows you to display ASCII characters in the form of a 5 by 7 or 5 by 8 matrix of LCD elements.
Graphics - In this display, rows and columns full of pixels are available that you can use to create whatever graphical or numeric or alphabetical information that you would like to display.

The following are the characteristics of LCDs:

The display technology works by manipulating light.
It Uses two polarizers - horizontal and vertical placed on top of each other with a source of light at the bottom
There is liquid crystal between the two polarizers
There is liquid crystal, when potential is applied, have the ability to 'twist' the light

16*2 character display can be operated in two modes:-

8 Bit mode - This is the default mode in which all the data pins are used
4 Bit mode - In this mode, only four data pins are used