Reference no: EM132505631

1007ICT/7611ICT Computer Systems and Networks Assignment - Griffith University, Australia

Task Description - You are to build (and test) the following digital logic circuit in the Logisim simulator and write a short report that describes your circuit. The maximum mark that you are able to achieve on the assignment will be determined by the difficulty of the circuit you decide to build.

Templates/Subcircuits - You will be required to use templates (Logisim calls these subcircuits) to simplify the overall circuit design.

Testing - You will need to test various possible combinations for the inputs V 1, V2 , V3, A1, A2 and A3 and check if the desired output is obtained (for Part A). You do not need to submit your tests.

For Part B, you will also have to test the case s where the speed simulation ends.

Report - Your report (6 -8 pages including diagrams ) must have the following sections:

1. Your details: Name, student number, and email address

2. Circuit Function: A brief (100-200 words for each part ) description of the function of each separate part of your circuit describing in your own words how that part of the circuit operates. This should be split up into sections that relate to the different components (templates/subcircuits) in the overall circuit.

3. Circuit diagrams: A diagram of your circuit including all templates /subcircuits and their contents. You must draw this diagram yourself using the Logisim logic simulator. To include a circuit in your report, please t ake a screen shot (using the Windows snipping tool or equivalent) of the circuit and paste the screenshot into your report. Copying and pasting from the lecture notes or other sources is NOT permitted.

4. Truth table: Show all possible combinations for the Velocity (V) and the Acceleration (A). The column headings in your truth table should correspond to the labels on your circuit diagram.

Requirements -

For this assignment you must implement a simple simulation of the velocity (speed) of a car. The simulation has two inputs. Input 1 (V) represents the Current velocity (0 -7). Input 2 (A) represents the acceleration (or deceleration) and the resulting velocity change in a single time unit of the simulation.

An A value of 1, 2, or 3 means the car decelerates (reduces its velocity) by 1, 2, or 3 velocity units. The acceleration is successful if the final Velocity is in the range 0 -7, where 0 is stopped, and 7 is maximum velocity.

An A value of 4, 5, or 6 means the car accelerates (increases its velocity) by 1, 2, or 3 Velocity units. The acceleration is successful if the final Velocity is in the range 0 -7 where 0 is stopped, and 7 is maximum velocity.

An A value of 0 means there is no change to the Velocity. This acceleration will always be successful.

An A value of 7 means that the turbo button has been pressed and the Velocity moves to its maximum value (7). This acceleration will be successful if the current velocity is not 0.

Note: The examples on this page represent only some selected cases. There are (many) more cases that result in successful or unsuccessful accelerations. Your circuit must correctly show a successful or unsuccessful acceleration for each possible case.

V and A Inputs -

Part A - Circuit Option 1: Part A Only

The implementation for this part must use only the three basic logic gates (AND, OR, NOT) with maximum 2 inputs. No other logic gates or circuits are permitted.

You are required to implement a circuit where the user (you) can input a value for the Velocity (V) using value (V1, V2, and V3) and an acceleration to apply (A) using value (A1, A2, and A3) and the circuit decodes the V1, V2, V3 and A1, A2 , A3 values using a decoder (see lecture notes) made up of only the permitted logic gates to determine if the acceleration is successful or unsuccessful based on the requirements section on page 4 is met.

The output is via a single LED labelled Successful which is lit if V = 0, 1, 2, 3, 4, 5, 6, or 7 after a successful acceleration is applied (A = 0, 1, 2, 3, 4, 5, 6, or 7). The LED is not lit for any values of V or A or where the applied acceleration is unsuccessful.

Part B - Circuit Option 2: Part A and Part B

For this part, the simulation will count how many successful and unsuccessful accelerations have been made, If the number of unsuccessful accelerations becomes greater than the number of successful accelerations the simulation must stop and no changes to the circuit will be permitted after this happens.

Using the same circuit as Part A , add additional circuitry to count how many successful and unsuccessful accelerations have been tried . Each time an unsuccessful acceleration is tried, add 1 to the number of unsuccessful accelerations. Each time a successful acceleration is tried, add 1 to the number of successful accelerations.

Simulation stopping condition (simulation output cannot change):

If the number of unsuccessful accelerations is greater than the number of successful accelerations t hen an LED labelled "Circuit locked" is lit, and the circuit is permanent ly locked. No matter the changes to the input s after this happens, the "Simulation locked" LED will remain lit and cannot be turned off.

Note: If the successful count reaches the maximum value of 7 (for a 3 bit counter) then the simulation will also stop but the 'Simulation Locked' LED will remain off. In this case you can assume that the user will no longer try to interact with the simulation.

For Part B only, you may use only the three basic logic gates (AND, OR, NOT) with maximum 2 inputs, as well as the more advanced counter (3 bit), comparator (3 bit unsigned) , and DFLIP -FLOP circuits (only those three ) from the Logisim circuit library. You may also use constant s. The prebuilt DFLIP -FLOP circuit can be used to 'remember' some information.

Note: For Part B you will need to add a button that is pressed by you after the Velocity (V) and acceleration (A) have been entered. This is to avoid counting while you are adjusting the input pins for the V and A input pins (V1, V2, V 3, A1, A2, and A3).

Additional requirement - This extra section is required to be completed regardless of whether you chose to complete Part A or Part B and should be about 400-6 00 words in length.

In this section, give a detailed description of the following:

1. How you would need to change the circuit if the Velocity (V) and acceleration (A) were for a car that could also have negative velocity values of -1, -2, -3 and -4?

2. How you would need to change the circuit if the turbo acceleration (7) was not permissible if the velocity was negative?

3. How would you need to change the circuit if the car could not physically change velocity by more than 1 unit at a time because of limitations of the gearbox? In other words only an A value of 1 and 4 will result in a successful velocity change.

Attachment:- Computer Systems and Networks Assignent File.rar