Digital clock using RTC DS12C887 and 8051 microcontroller (AT89C51) with time set
Real time clock (RTC) is widely used in many application to provide accurate time. This article explains the making of a simple digital clock using RTC DS12C887 and 8051 microcontroller (AT89C51). The output is displayed on an LCD. This clock also has a provision of setting time at any instant. The clock uses the concept of our earlier articles of interfacing RTC DS12C887 with microcontroller. The clock described here uses the method of polling for running. For further details on interfacing RTC DS12C887 with AT89C51 using polling, refer RTC interfacing. The free source code for the program is available in C.
The circuit diagram shows the connection of RTC with the microcontroller. Port P2 is used as data port for LCD; port P0 of the microcontroller is used as data port of RTC DS12C887. The pins P1^0, P1^1, P1^2, P1^3, P1^4, P1^5, P1^6 of controller AT89C51 are configured as reset, rs, rw, e, dig_hr1, dig_min1, start pins respectively.
LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range of applications. A 16x2 LCD display is very basic module and is very commonly used in various devices and circuits. These modules are preferred over seven segments...
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...