The document introduces the 8051 microcontroller, an 8-bit single-chip CPU from Intel, launched in 1981 with 128 bytes of RAM, 4KB of ROM, and various peripherals. It details the architecture, including its 40-pin configuration, timers, and ports, along with specific manufacturing information like the Atmel AT89C51 series. Additionally, the document mentions the use of Keil software for programming the 8051, providing a simple example of LED blinking code.

1. By: Priyanka
Patidar

2. Introduction of 8051
 8051 is single on chip controller or a CPU with all
the peripherals like RAM, ROM, I/O ports, Timers
etc on the same chip.

3. History of 8051
 In 1981 (Intel company) introducing 8-bit
microcontroller having RAM 128 bytes, ROM 4k bytes,
2 Timers (T0,T1), 1 serial port (2 pins – TxD, RxD) and 4
I/O ports on a single chip (P0,P1,P2,P3).
 8051 microcontroller can work on only 8-bits of data at a
time.

4. Architecture

5. Features of 8051
It is useful for a small computing task and adequate for many
controlling and monitoring applications.
ROM 4 k bytes
RAM 128 bytes
Timers 2
I/O Ports 32
Serial ports 1
Interrupt sources 6

6. Manufacturing
 AT89C51 from Atmel Corporation—
AT89C51-12PC C52,S51,S52)
 89- manufacturing’s series
 S-silicon CMOS
 C-CMOS, which has low power consumption 12-12
MHz
 P-Plastic DIP package
 C-Commercial
 51/52 –Family of 8051

7. Pin description
 8051 has 40 pins
 Total of 32 pins are set into 4 ports such as P0,P1,P2,P3.
each contains 8 pins.
 PS0C= system on chip
 2 Timers- Timer 0 & Timer 1
 2 pins fro crystal oscillator – XTAL1 &XTAL2
 1 pin is GND and 1 pin is VCC

9. Keil software
 It is a open source software platform to program your
embedded system.
 First install Keil set 8051 of micro version 5 (update
version).

11. Single LED Blinking
 #include <reg51.h>
 Sbit led=P1^0;
 Unsigned int i;
 Void main()
{
while(1)
{
led1=1;
for (i=0;i<=25000;i++);
led1=0;
for(i=0;i<=25000;i++);
}
}