The success of the Intel 8051 spawned a number ofclones which are collectively referred to as the MCS-51 family of microcontrollers,which includes chips from vendors such as Atmel, Philips, Infineon, and TexasInstruments.

- Interrupts, as their name implies, allows for external events (such asinputs from the user or AVR peripheral) to momentarily pause themain microcontroller program.

- The AVR has a clock that “ticks” at a regular rate. A variety ofclocks types and speeds are available, including a built-in circuit orexternal crystals.

- #include<REGx51.h> //header file for 89C51 void main(){ //main function starts unsigned int i; //Initializing Port1 pin1 P1_1 = 0; //Make Pin1 o/p while(1){//Infinite loop main application//comes herefor(i=0;i<1000;i++);//delay loopP1_1 = ~P1_1;//complement Port1.1}}

- serialization is the process of translating data structures or objectstate into a format that can be storedand reconstructed later in the same or another computerenvironment