I am really stuck here, our instructor told us not to use the 555 timer (and to be honest I never used it). So we are supposed to make a circuit by using counters only, I guess.
How can I generate time periods, and set time in seconds or minutes? Is Johnson Counter the best to use here?
I included the project needed and the periods I made, if any one could help me on that. My project is due to next Monday, and I would be really grateful if someone could give me an idea or a hint to start.
The Project: Design a digital circuit that can be attached to a school bill which can work automatically from 7:00 AM to 12:45 PM, and it has the following features
1- Rings for 5 seconds.
2- Start ringing 7:00 AM to announce for the field gathering.
3- Rings 7:20 for going to class.
4- Rings for the start of the first class period at 7:35 AM.
5- Rings for end of each period after 40 minutes from its start.
6- Rings for break after 10 minutes from the end of the previous period to announce for the next class period.
7- After the third period, a break of 30 minutes.
*The Bell rings for 5 seconds.
7:00 AM (Ring for field gathering)
7:20 AM (Ring for going to class)
7:35 AM (Ring for the 1st class START)
8:15 AM (Ring for the 1st class END)
8:15 AM – 8:25 AM (Break for 10 minutes)
8:25 AM (Ring for the 2nd class START)
9:05 AM (Ring for the 2nd class END)
9:05 AM – 9:15 AM (Break for 10 minutes)
9:15 AM (Ring for the 3rd class START)
9:55 AM (Ring for the 3rd class END)
9:55 AM – 10:25 AM (Break for 30 minutes)
10:25 AM (Ring for the 4th class START)
11:05 AM (Ring for the 4th class END)
11:05 AM – 11:15 AM (Break for 10 minutes)
11:15 AM (Ring for the 5th class START)
11:55 AM (Ring for the 5th class END)
11:55 AM – 12:05 AM (Break for 10 minutes)
12:05 AM (Ring for the 6th class START)
12:45 AM (Ring for the 6th class END)