NetDisp

Introduction
Building
Examples
Notes
Images

Introduction

NetDisp is an ESP32 based wireless network display (currently only SSD1306) that allows to show text and graphics received via UDP.

Data can be sent to the display either in form of an ASCII string, which will show the data as (formatted) text or binary in form of specific commands which also allows to control the LEDs or show images on the display. The is display designed to be generic to allow various applications within the same network to present information their information. For that the display provides a set of virtual displays that can either be manually selected or via commands send to the display. Each virtual display can be individually updated and controlled even if it is currently not visible.

After starting up and estabilishing a wireless connection the display will show "Ready" together with it's IP address and port (see images). The display is now ready to receive commands, this can be done for example using netcat:

echo "Hello World" | nc -b -w 0 -u <ip> <port>

Alternatively also a python implementation is provided to control the display:

from netdisp import NetDisp
netdisp = NetDisp("<ip>", "<port>")

netdisp.show_text("Hello World").send()
netdisp.show_image(0, 0, 128, 64, "/path/to/image").send()

Building

Software

This project uses ESP-IDF v4.2 as the development framework, to build the project it is required to have ESP-IDF installed.

Install ESP-IDF:

git clone --recursive https://github.com/espressif/esp-idf
cd esp-idf
git checkout v5.1
git submodule update --init --recursive

Clone the project:

git clone --recursive https://github.com/Manewing/netdisp.git

To build simply run:

source <path/to/esp-idf>/export.sh
cd netdisp/
idf.py build

To build and run tests run:

mkdir build_test
cd build_test
cmake ../test
make
ctest

Python

Install the requirements:

pip install -r requirements.txt

Running build will also copy the python files to the build directory, these can be dynamically added to the environment by running:

source build/exports
# "import netdisp" should now work

Configuration

The NetDisp project can be configured by running:

idf.py menuconfig

This allows to set configuration values such as the SSID and password of the WLAN access point to use or the used GPIO pins.

Hardware

Components:

0.96" 128x64 SSD1306 OLED
ESP32 NodeMCU Modul
Rotary Click Encoder Module KY-040
3D Printed Casing and Nob
Green and Red 3mm LED
M2 Screws: 4*M2 x 4mm, 22*M2 x 10mm

The STL models for 3D printing can be found in the folder 3d_models. In the folder is also a Fusion 360 export of the project.

Examples

Example applications can be found in the sub-folder examples/ these include:

A Crypto Currency Tracker
A System Monitor
Simple text and formatting

Notes

At the momemnt the display does not provide any form of authentication or security. This means anyone in the network can control it.
This project is inspired by this project from hackaday.io