A microprocessor is a general-purpose digital computer for the central processing unit. To make a complete microcomputer, you add memory (ROM or RAM) memory decoders,an oscillator, and a number of I/O devices. The prime use of a microprocessor is to read data, perform extensive calculations on that data, store the results in a mass storage device, or display the results. The design of the microprocessor is driven by the desire to make it as expandable or flexible as possible.
microcontroller is a general-purpose device meant to read data, perform limited calculations on that data, or control its environment based on those calculations. The prime use of a microcontroller is to control the operations of a machine using a fixed program that is stored in ROM or does not change over the lifetime of the system. The microcontroller is concerned with getting data from or to its own pins; the architecture or instruction set is optimized to handle data in bit or byte size.
1. RXD (pin-10):0th pin of PORT P3 or Receiver pin of Microcontroller
2. TXD (pin-11):1st pin of PORT P3 or Transmitter pin of Microcontroller
3. INT0 (pin-12):2nd pin of PORT P3 or External Interrupt 0 of MCU
An electronic digital clock, as opposed to an analog clock using a mechanical fitting to indicate the time of the occurrences, is a timepiece that displays the time digitally. Digital clocks are used in practically every aspect of our lives or may be found in a variety of locations such as homes, hospitals, schools, or companies. So, in this article, we will use the Atmel AT89C2051 of the controller to create a 4-bit Electronic Digital Clock.
The Atmel AT89C2051 is an 8051-based Fully Static 24MHz CMOS of the controller with 15 I/O Lines, 2 Timers/Counters, 6 Interrupts/2 Priority Levels, Analog Comparator, LED Drive Outputs, UART, 2-level Program Memory Lock, 2K Bytes Flash Memory, 128 Bytes On-chip RAM.
The AT89C2051-24PU is a CMOS 8-bit microcontroller in a 20-pin DIP package with a low voltage or great performance. The device is made with high-density nonvolatile memory technology or is compatible with the MCS-51 instruction set, which is widely used in the industry. It combines a versatile eight-bit CPU with flash on a monolithic device to deliver a highly adaptable or cost-effective solution for a wide range of applications. On-chip analog comparator, on-chip oscillator, clock circuits, low power supply idle, and power-down modes are all included in the AT89C2051-24PU. This microcontroller features static logic for operating at low frequencies and 2- software-selectable power supply-saving modes. The power supply-down option saves RAM data but freezes the oscillator, effectively shutting off all chip functions until the next hardware reset.
To ensure that the display of the control lines is in a known state before they are latched, an AT89C51 external interrupt is used to allow the programmer to signal the application before asserting reset. The application firmware responds to the interrupt by displaying a message and deactivating the display of the control lines.
The AT89C1051 provides the following standard features: 1K Byte of Flash, 64 bytes of RAM, 15 I/O lines, one 16-bit timer/counter, a 3-vector two-level interrupt architecture, a precision analog comparator, an on-chip oscillator, or clock circuitry.
AT89c51 Microcontroller: Programming, Pinout, Features, or Alternatives. The Atmel AT89 series falls under the 8-bit microcontroller family compatible with Intel 8051. Their advantages include cost-effectiveness and high flexibility when used in embedded control of the applications.
A microcontroller is embedded inside a system to control a singular function in a device. It does this by interpreting the data it receives from its I/O peripherals using its central processor.
8051 microcontroller is a 40-pin Dual Inline Package (DIP). These 40 pins serve different functions like read-write, I/O operations, interrupts, etc. 8051 has four I/O ports wherein each port has 8 pins which can be configured as input and output depending upon the logic state of the pins.