DS1302 RTC 8051 Digital Clock Circuit (LCD Display)

8051 keil example application circuit LCD Display Digital Clock using DS1302 RTC General Information About MicrocontrollersMicrocontroller: It is an electronic element that makes no sense without installing a software. When there is software that controls the microcontroller, it has almost unlimited applications.

Microcontrollers have many advantages over microprocessors. For example, when a system with a microprocessor is made, besides the microprocessor, memories (RAM, ROM or EPROM), I/O unit and many similar systems are used. This complex system is both difficult to design and construct, and the cost is quite high. In microcontrollers, only a microcontroller and oscillator circuit may be sufficient to operate a system. The cache and I/O unit required in the system are in the form of a chip in microcontrollers.

Microprocessor: It is the unit that runs the program written in its cache and directs it to the desired outputs. Microprocessor or digital computers consist of three basic parts (CPU – Central processing unit, I/O and memory) plus some supporting circuits. Each fundamental part ranges from the simplest to the most complex.

INPUT / OUTPUT (I/O): It consists of digital, analog and special functions. It provides the relationship of the microprocessor with the outside world. The data given to the microprocessor and received from the processes are provided over this line.

CPU (Central Proccesing Unit): It is the heart of the system. It works in 4, 8 or 16 bit data format to make unit calculations and handle data. There are basically three ways a microprocessor is used;

1) Data bus: This bus is used to transmit data between the processor, memory and peripherals.

2) Address bus: This bus is used to send the memory addresses that provide access to the program instructions and data storage areas of the processor to the ROM and RAM memories.

3) Audit path: This path is used for audit purposes, such as informing that data is being written to or read from the RAM memory. This path also contains links that allow the use of interrupts. Execution of a typical microprocessor instruction may require the use of all three paths. Thus, the additional circuits used increase in cost and the design becomes very complex.

The processor first accesses the instruction by putting the instruction address in the address bus. This address, which consists of binary codes, is recognized by the corresponding memory location and this location sends the requested command over the bus to the processor. For example, if this instruction requires that data be sent from the processor and stored in a RAM location, the processor is used to specify the address bus to the desired location, transmit data to the bus, and indicate that it is writing the control bus to RAM.

8051 Digital Clock Schematic

8051 Digital Clock Circuit keil source code and proteus isis simulation schematic files: author: @Aytan ASLAN