need books about digital clock circuit based fpga

Hi Anssam, salam

You need an altera development board and its data sheet should give good guide. Digital clock should be straighforward. You need to run a clock inside fpga, then convert it to 1 sec pulse using counter, then use three more small counters. one for seconds (0~59), one for minutes(0~59), one for hours (0 ~ 23 or 0 ~ 11).

What is left is read these counters and decode values for display.

As you work through, we can help here.

Wa domtom