a. Identify how many inputs do you have, and how many outputs. Identify how many states you need. Hint: Start with an initial state of 00. What happens if D is asserted? What if another D is asserted? Go through all the available scenarios for your inputs. b. Draw an FSM state diagram. c. Create the output table and next state tables. d. Create K-maps to minimize your next state and output tables. e. Use the K-maps to generate a logical expression

The gumball machine delivers a piece of gum after receiving 15 in coins. The machine has a single coin slot that accepts nickels and dimes, one coin at a time. A mechanical sensor indicates to the control whether a dime or a nickel has been inserted into the coin slot. The input N is asserted when a nickel is inserted into the coin slot. Dis asserted when a dime is deposited. The machine asserts OPEN for one clock period when 15 or more has been deposited since the last reset. Then the controller's output causes a single piece of gum to be released down a chute to the customer. The machine does not give change. A customer who pays with two dimes get a piece of gum, but overpays 5. The machine does not accept coins it does not recognize, either. Using a diagram the gumball machine can be viewed as follows: OPEN N Coin sensor Gum dispenser FSM Gum release mechanism D CLK N is asserted for 1 clock period when a nickel is inserted into the coin slot. Dis asserted for 1 clock period when a dime is inserted into the coin slot. Machine asserts Open when 15 or more has been deposited. You may assume that once the gum is dispensed, we need to manually reboot the machine, so no need to worry about what happens afterwards. The gumball machine delivers a piece of gum after receiving 15 in coins. The machine has a single coin slot that accepts nickels and dimes, one coin at a time. A mechanical sensor indicates to the control whether a dime or a nickel has been inserted into the coin slot. The input N is asserted when a nickel is inserted into the coin slot. Dis asserted when a dime is deposited. The machine asserts OPEN for one clock period when 15 or more has been deposited since the last reset. Then the controller's output causes a single piece of gum to be released down a chute to the customer. The machine does not give change. A customer who pays with two dimes get a piece of gum, but overpays 56. The machine does not accept coins it does not recognize, either. Using a diagram the gumball machine can be viewed as follows: OPEN Coin N Gum Gum release sensor dispenser mechanism FSM D CLK N is asserted for I clock period when a nickel is inserted into the coin slot. . Dis asserted for I clock period when a dime is inserted into the coin slot. Machine asserts Open when 15 or more has been deposited. . You may assume that once the gum is dispensed, we need to manually reboot the machine, so no need to worry about what happens afterwards. The gumball machine delivers a piece of gum after receiving 15 in coins. The machine has a single coin slot that accepts nickels and dimes, one coin at a time. A mechanical sensor indicates to the control whether a dime or a nickel has been inserted into the coin slot. The input N is asserted when a nickel is inserted into the coin slot. Dis asserted when a dime is deposited. The machine asserts OPEN for one clock period when 15 or more has been deposited since the last reset. Then the controller's output causes a single piece of gum to be released down a chute to the customer. The machine does not give change. A customer who pays with two dimes get a piece of gum, but overpays 5. The machine does not accept coins it does not recognize, either. Using a diagram the gumball machine can be viewed as follows: OPEN Coin Gum Gum release sensor dispenser mechanism N D FSM CLK Nis asserted for 1 clock period when a nickel is inserted into the coin slot. . Dis asserted for I clock period when a dime is inserted into the coin slot. Machine asserts Open when 15 or more has been deposited. You may assume that once the gum is dispensed, we need to manually reboot the machine, so no need to worry about what happens afterwards