Retro RTC

5th of April'10
<1130>Got up after a long sleep.
<1200-1300>WTH was I doing then? Probably taking some pills for having a good memory huh!
<1330>Had lunch.
<1600>Came back to room.
<1630> A KNOCK at my door.
A friend of mine was asking for some assistance in his mini project. I thought it would be fun and started discussing about it. It's a retro RTC (Real Time Clock). The fact that I call this a retro is that he didn't want to use any RTC chip and he brought an AT89C2051 microcontroller for this 24 hour clock project.
<1700> Project started.

It has a timer facility as well. The relay in the above picture is to drive a load connected to AC mains. A timer can be set to switch on and off the load automatically at a particular time.Starting from top to bottom in the picture, the first switch is to set Hour, the next one for min, the third one for timer on off and the last one for manual on/off switch. For the load to have a normal operation when the whole device is off, it is connected to NC (Normally closed) and Common pins. He wanted to have power supply from AC mains. He had brought all the stuffs for that so finished that part as well.

And finally.............

Timer mode on/off

I covered the display with a polythene bag to give a better look ( I didn't have anything better at that point of time).

<1900> Project Completed!