How to Interface RTC DS12C887 with 8051 microcontroller (AT89C51)
The purpose of an RTC or a real time clock is to provide precise time and date which can be used for various applications. RTC is an electronic device in the form of an Integrated Chip (IC) available in various packaging options. It is powered by an internal lithium battery. As a result of which even if the power of the system is turned off, the RTC clock keeps running. They play a very important role in the real time systems like digital clock, attendance system, digital camera etc.
This project uses the method of polling to read the data from the RTC. In this method the data is continuously scanned and sent to hyper terminal for display. The connections of RTC DS 12C887 and serial port (RS232) with the 8051 microcontroller (AT89C51) are shown in the circuit diagram.
The MAX232 IC is used to convert the TTL/CMOS logic levels to RS232 logic levels during serial communication of microcontrollers with PC. The controller operates at TTL logic level (0-5V) whereas the serial communication in PC works...
RTC DS 12C887 is widely used to provide exact time and date in many applications such as x86 IBM PC. This RTC provides time components hour, minute and second in addition to the date/calendar components of year, month and day. This chip uses an internal lithium battery, which keeps the time and da...