This assignment involves designing the architecture and writing RTL for an elevator controller in

a building with five floors $($a ground floor and four upper floors$).$

The elevator should manage multiple requests simultaneously by assigning priority. The elevator

should prioritize requests in its current direction of movement, servicing requests in the upward

direction while moving up$,$ and downward while moving down. If the elevator is idle $($not

moving$),$ priority is given to the first floor requested. If multiple requests are received at the

same time while the elevator is idle, priority is given to the highest floor among the requests.

The elevator includes a stop feature: a push button inside the elevator allows passengers to stop

it immediately. When pressed, the elevator halts and retains all input, output, and control

states. Pressing the button again releases the stop, allowing the elevator to resume from where

it left off, with all signals and states preserved for a seamless continuation.

Floor requests can be made via push buttons located on each floor or from buttons inside the

elevator $.$ The elevator takes $2$ sec$.$ to travel between two consecutive floors. The door stays

open for $2$ sec$.$ on the floor $.$ Elevator Controller

System Description

This assignment involves designing the architecture and writing RTL for an elevator controller in a building with five floors $($a ground floor and four upper floors$).$

The elevator should manage multiple requests simultaneously by assigning priority. The elevator should prioritize requests in its current direction of movement, servicing requests in the upward direction while moving up$,$ and downward while moving down. If the elevator is idle $($not moving$),$ priority is given to the first floor requested. If multiple requests are received at the same time while the elevator is idle, priority is given to the highest floor among the requests.

The elevator includes a stop feature: a push button inside the elevator allows passengers to stop it immediately. When pressed, the elevator halts and retains all input, output, and control states. Pressing the button again releases the stop, allowing the elevator to resume from where it left off, with all signals and states preserved for a seamless continuation.

Floor requests can be made via push buttons located on each floor or from buttons inside the elevator. The elevator takes $2$ sec $.$ to travel between two consecutive floors. The door stays open for $2$ sec $.$ on the floor.

For simplicity, we assume both the external and internal request signals are $5-$bit vectors, indexed from $0$ to $4$ to represent each floor. Each bit corresponds to a specific floor: bit $0$ represents the ground floor, bit $1$ represents the first floor, and so on$.$ For example, if external requests come from the first and third floors, i$\_$req$\_$ext would be $5\text{'}$b$01010.$ Similarly, if internal requests come from the second and ground floors, i$\_$req$\_$inter would be $5\text{'}$b$00101.$ The combined request vector would then be $5\text{'}$b$01111.$ Requests are granted in the prioritized order specified above. Signals

Table $1$

$\backslash$begin$\{$tabular$\}\{|$c$|$c$|$c$|$l$|\}$

$\backslash$hline Signal & Width & Direction & $\backslash$multicolumn$\{1\}\{$c$|\}\{$ Description $\}\backslash \backslash$

$\backslash$hline i$\_$clk & $1$ & Input & Positive edge system clock $(50$ MHz$)\backslash \backslash$

$\backslash$hline i$\_$rst$\_$n & $1$ & Input & Negative edge asynchronous system reset $\backslash \backslash$

$\backslash$hline i$\_$req$\_$ext & $5$ & Input & $\backslash$begin$\{$tabular$\}\{$l$\}$

External input requests where each bit represents the $\backslash \backslash$

push button outside the elevator for its corresponding $\backslash \backslash$

floor. When a bit is set to $1,$ it indicates a request from $\backslash \backslash$

that floor.

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline i$\_$stop & $5$ & Input & $\backslash$begin$\{$tabular$\}\{$l$\}$

Internal elevator requests where each bit represents a $\backslash \backslash$

push button inside the elevator for a specific floor. $\backslash \backslash$

When a bit is set to $1,$ it indicates a request for that $\backslash \backslash$

floor.

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline o$\_$current$\_$floo & $3$ & output & $\backslash$begin$\{$tabular$\}\{$l$\}$

A stop button inside the elevator allows People to $\backslash \backslash$

immediately halt the elevator.

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline o$\_$up & $1$ & $\backslash$begin$\{$tabular$\}\{$l$\}$

An output indicating the current floor number. For $\backslash \backslash$

example, if the elevator is on the third floor, $\backslash \backslash$

o$\_$current$\_$floor will be set to $3\text{'}$d$3.$

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline output & $\backslash$begin$\{$tabular$\}\{$l$\}$

$1$: elevator is moving up $\backslash \backslash$

$0$: elevator is moving down or not moving

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline o$\_$door & $1$ & output & $\backslash$begin$\{$tabular$\}\{$l$\}$

$1$: elevator is moving down $\backslash \backslash$

$0$: elevator is moving up or not moving

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline output & $\backslash$begin$\{$tabular$\}\{$l$\}$

$1$: elevator door opens $\backslash \backslash$

$0$: elevator door closed

$\backslash$end$\{$tabular$\}\backslash \backslash$

$\backslash$hline

$\backslash$end$\{$tabular$\}$

Deliverables

You have to submit a pdf or zip file that contains:

$-$ A PDF file that contains:

$-$ Architecture of the design which includes how sub$-$blocks communicate with each other.

$-$ Description of the operation between blocks and any existing FSM

$-$ Simulation waveform that shows the module is working correctly.

$-$ Project folder contains $($zip file or google drive link$)$:

$-$ RTL codes of the system.

$-$ Testbench code of the system.

Eng. Yousef