This article is an improved variant of Digital clock using RTC DS12C887 and 8051 with time set. In the earlier article, we discussed the basics of extracting data from [[wysiwyg_imageupload::]]the RTC DS12C887 using the 8051 microcontroller (AT89C51). This article is in continuation to the above article and introduces you to the concept of handling interrupts for extracting time and other information from the RTC.Interrupts offer a great flexibility to handle RTC. Interrupts have several advantages over the method of polling as discussed in the previous article. It reduces the unnecessary usage of microcontroller’s memory and processing powers, thereby keeping the processor free for other use. RTC 12C887 has three interrupts, namely, Alarm interrupt, Periodic interrupt & Update ended interrupt. For detailed information, check RTC interrupts. The free source code for the program is available in C.This article assumes that the user is aware of real time clock and the basic interfacing of DS12C887 with 8051 microcontroller (AT89C51) including the pin description, memory and registers of RTC DS 12C887.