Do have interface the any rtc ever.
I was interface with new rtc but i have holtech rtc ht1380 but i was not able to locate the datasheet for this chip so i wasn`t go fo prog. if you have it send it to me
i try my best to help you.
Dear Manish,
I am also looking for interfacing code of RTC HT1380 with µ 89C51 in assembly codes. As you are saying for datasheet of the RTC. Hence attached the same. Pl help if possible.