Design a vending machine controller as a digital system by using the finite state machine (FSM) technique .A vending machine controller delivers gums and chips, both costing 35 rupees. One can input only Dimes (10 rupees) and Nickels (5 rupees). There is no Coin Return button. After receiving the necessary amount (35 rupees or 40 rupees), deliver
Gum or chips after the selection is made and return 5 rupees if necessary.

 

We cant just do the work for you. However we can help.
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sir i have jst started and i want some help that how should i initiate........
........this problem because i don't have any idea about this.......so please lead me.......

 

The vending machine will be implemented with a sequential design and implemented with 74xx series logic

 

A popular homework subject:

http://forum.allaboutcircuits.com/showthread.php?t=26160
http://forum.allaboutcircuits.com/newsgroups/viewtopic.php?p=95718
http://forum.allaboutcircuits.com/newsgroups/viewtopic.php?p=98064

Also, just search this forum for "vending."

John