Project Overview
In this Deli Counter project we were tasked with the painstaking, yet splendiferous designing of a circuit that will do all of the following 3 things.
1. Count up from 0-80
2. Stop automatically at 80
3. Have a manual reset that reset both values to 0
1. Count up from 0-80
2. Stop automatically at 80
3. Have a manual reset that reset both values to 0
Design vs PLD mode
Design mode in Multisim is a mode were you can design circuits and test them. In this mode you can simulate a circuit just as they will be in real life. It can help you learn and understand the functions or parts of the circuits or, it can be used for troubleshooting. PLD differs from this mode in some ways though. In PLD you can simulate circuits like you do in design mode but, the interface changes a little and you are now allowed assign different parts of the circuit to output or input pins. These features are typically used in conjunction with a certain device that you can upload your circuit to, eliminating the use of individual chips.
Conclusion
- The difference between Small Scale Integration and Medium Scale Integration is the size of the integration, as implied in the small and medium descriptions of the integration. SSI typically is around 10 gates, while MSI can be 100 gates or less.
- Our circuit in this Deli counter was a MSI circuit. It did have some limitations that we had to work with. Some examples are that the 74ls93 chip that we used can only count up, it only start at 0, and it can only have up to 4 bits.
- When I start my simulation of the circuit, the ones place starts to count because of the clock that is connected to the 74LS93 circuit. The clock of the circuit is connected through a logic of expression in order to make the count suspend at 80 as soon as it is detected. The clock is connected to one input of the AND gate and the other input is a logic expression that will show a 1 every time except for when an eight is detected on the 74LS74 chip, and a zero is the output and the circuit suspends. The 74LS93 chip is a 4 bit up counter that starts at zero. It needs to detect a 10 in order to display a 9 on the hex display. Every time a 9 is detected the display will reset back to zero. The output of that segment is connected to the clock of the tens place therefore driving the tens place up one every time the ones place resets to 0. Both reset logic expressions are connected with an AND gate, so that a reset switch can be hooked up that will reset both displays back to zero when the circuit is broken. When all of these are put together the circuit will count to 80, suspended 80, and reset whenever the reset switch is low.
- Yes some my classmates had different circuit designs, for example, my fellow classmate, Silas Cascio, used a different logic expression to connect the two individual circuits together. The different designs did work still.