# I need assistance asap, assignment due in 4 hours. Elevator circuit.

#### ardie123

Joined May 9, 2019
3
Hey there, if anyone would like to help the question is:

For this assignment you must implement a simple simulation of an elevator. The elevator has two inputs. Input 1 (C) represents the Current floor (0-7). Input 2 (D) represents the Destination floor to move to (0-7). The elevator is only allowed to stop on Floors 1, 2, 3, 5, and 7. Floors 0, 4 and 6 are private and the elevator will not stop there even if the button for that floor is pressed. The elevator movement is successful if C = 1, 2, 3, 5, or 7, D = 1, 2, 3, 5, or 7, and C ≠ D. Any other values will result in an elevator movement error and the elevator will not move.

Example 1: The current floor (C) is 2 and the floor we want to move to (D) is 5. In this case the move to floor 5 is successful.

Example 2: The current floor (C) is 2 and the floor we want to move to (D) is 4. In this case D is 4 (a private floor) and there is an elevator movement error. The elevator does not move.

Example 3: The current floor (C) is 4 and the floor we want to move to (S) is 2. In this case the starting floor is 4 (a private floor) and there is an elevator movement error.

The elevator does not move Note: These are just a couple of examples. There are (many) more cases that result in successful or unsuccessful elevator moves. Your circuit must correctly show a successful or unsuccessful elevator move for each possible case. The Current floor (C) will be represented by three inputs (3 bits). The three C inputs are named as C1, C2, and C3.

Part A Only (35 marks): The implementation for this part must use only the three basic logic gates (AND, OR, NOT) with maximum 2 inputs. You are required to implement a circuit where the user (you) can input a value for the Current floor (C) using value (C1, C2, and C3) and a Destination floor to move to (D) using value (D1, D2, and D3) and the circuit decodes the C1, C2, C3 and D1, D2, D3 values using a decoder (see lecture notes) made up of only the permitted logic gates to determine if the requirement for moving in the requirements section on page 4 is met. The output will be a single LED labelled Successful which is lit if C = 1, 2, 3, 5, or 7, D = 1, 2, 3, 5, or 7, and C ≠ D. The LED is not lit for any other values of C and D.

#### gramps

Joined Dec 8, 2014
86

#### ardie123

Joined May 9, 2019
3
i need to build a circuit based on the specifications above

#### Sensacell

Joined Jun 19, 2012
2,917
Don't think anyone will do it for you.

Joined Jul 18, 2013
23,907
Cutting it rather fine to post with 4hrs notice, especially as this is the time when most regular posters here are thin on the ground. IOW its late!
I guess you don't have the option of PLC ladder logic?
Max.

#### ardie123

Joined May 9, 2019
3
this was my attempt, i can get example 3 to work

#### Attachments

• 1.9 KB Views: 14

#### WBahn

Joined Mar 31, 2012
26,398
Perhaps you could start by describing how you could break the problem down into smaller pieces and then describe how you might solve each of those pieces in turn and then describe how you might combine the solutions to the smaller pieces together to solve the overall problem.

This is a simple enough problem that there is still time to solve it before the deadline, but only if you approach it in an organized way.

#### atferrari

Joined Jan 6, 2004
4,470
You will definitely have to use the stairs for now.

#### jpanhalt

Joined Jan 18, 2008
11,088
I smell something and it is not sweat from hard work. This thread is identical to the one I cited in post #7. The questions are the same, user names are different, and the simulations are the same.

I have attached the text readable versions of the logisim attachments. They open with Eagle. "AAC New Full.txt is the simulation from this thread. "RBR1317 Full.txt" is from the earlier thread.

I did a Word document compare and got this message:

Perhaps the two threads should be combined?

#### Attachments

• 9.9 KB Views: 3
• 9.9 KB Views: 1

#### WBahn

Joined Mar 31, 2012
26,398
That the assignments are identical is not too much of a surprise. That the Logisim files are identical is a pretty strong indicator, however.

Since, supposedly, the assignment deadline has passed, both threads will likely die a natural death at this point.

#### Uilnaydar

Joined Jan 30, 2008
118
<mourns the death of another assignment thread>

#### dl324

Joined Mar 30, 2015
13,506
The implementation for this part must use only the three basic logic gates (AND, OR, NOT) with maximum 2 inputs.
It's a little cumbersome to be limited to a maximum of 2 inputs...

Joined Jul 18, 2013
23,907
.....Still stuck on the ground floor!
Max.

#### jpanhalt

Joined Jan 18, 2008
11,088
.....Still stuck on the ground floor!
Max.
More likely in the basement of his class from what I can tell.

For all my years, I never ever considered copying someone else's work (arrogance?). However, during the few years after retirement that I volunteered teaching chemistry at a local college, that is not so uncommon and was even approved by administration. Probably has to do with the "team" culture of today.

#### dl324

Joined Mar 30, 2015
13,506
For all my years, I never ever considered copying someone else's work (arrogance?).
I rarely needed additional help and if I did, I usually got it from the instructor. That was before the internet had been invented...

#### dl324

Joined Mar 30, 2015
13,506
this was my attempt, i can get example 3 to work
Your partial solution doesn't satisfy the problem requirements. You're not allowed to use NAND.

The implementation for this part must use only the three basic logic gates (AND, OR, NOT) with maximum 2 inputs.

#### djsfantasi

Joined Apr 11, 2010
7,913
Your partial solution doesn't satisfy the problem requirements. You're not allowed to use NAND.
View attachment 177408
I suspect that by now, his/her instructor has pointed that out.

#### jpanhalt

Joined Jan 18, 2008
11,088
Your partial solution doesn't satisfy the problem requirements. You're not allowed to use NAND.
View attachment 177408
Doesn't an AND + NOT = NAND? Simple substitution. Frankly, though, I didn't look at the copied work.

#### djsfantasi

Joined Apr 11, 2010
7,913
Doesn't an AND + NOT = NAND? Simple substitution. Frankly, though, I didn't look at the copied work.
Yeah, but does the TS know that?