Elevator server

In the TTK4145 elevator project the elevator hardware is communicated with over TCP. Every elevator expose a server that clients (elevator logic) can connect to. This repo contains the code for the server part of the elevator interface.

Usage

Dependencies

Hardware & comedi

For this program to work elevator hardware needs to be connected through an io card supported by comedi in the same way as it is in the NTNU real time lab. It is made specially to work with the elevator hardware in this lab, and it is not recommended to use this software for outside this lab. For a solution that will work outside the real time lab, have a look at one of the simulators (Simulator v2, Simulator v3).

Cargo & Rust

To compile and install the elevator server, cargo and rust is needed. Both are best installed by using rustup.

Install

If the software is not installed you can run cargo install ttk4145_elevator_server to run install it. If an old version is installed and you wish to upgrade to the newest version cargo install --force ttk4145_elevator_server will do.

Run

The server can be started by running elevator_server. Once started, the server will start listening on localhost:15657. You can then connect to it by using a client that adhers to the protocol.

Clients

Protocol

• All TCP messages must have a length of 4 bytes
• The instructions for reading from the hardware send replies that are 4 bytes long, where the last byte is always 0

• The instructions for writing to the hardware do not send any replies

  Write

Writing | command[0] | command[1] | command[2] | command[3] ----------------------|----------------------|-------------------------|----------------------|-------------------- Reserved | x | x | x | x Motor direction | 1 | direction[-1(255),0,1] | x | x Order button light | 2 | button[0,1,2] | floor
[0..NF] | value[0,1] Floor indicator | 3 | floor[0..NF] | x | x Door open light | 4 | value[0,1] | x | x Stop button light | 5 | value[0,1] | x | x

Read

Reading | command[0] | command[1] | command[2] | command[3] | response[0] | response[1] | response[2] | response[3] ----------------------|--------------|---------------|---------------|--------------|---------------|---------------|---------------|--------------- Order button | 6 | button[0,1,2] | floor[0..NF] | x | 6 | active[0,1] | 0 | 0 Floor sensor | 7 | x | x | x | 7 | at floor[0,1] | floor[0..NF] | 0
Stop button | 8 | x | x | x | 8 | active[0,1] | 0 | 0 Obstruction switch | 9 | x | x | x | 9 | active[0,1] | 0 | 0