Sunday, October 29, 2017

Fast partial refresh on 4.2" E-paper display from Waveshare / Good Display



Google Drive link with Arduino firmware used in this project: https://drive.google.com/open?id=0B4YXWiqYWB99UmRYQi1qdXJIVFk



I bought the Waveshare devices on Aliexpress: https://www.aliexpress.com/item/400x300-4-2inch-E-Ink-display-module-SPI-Without-backlight-Compatible-with-variuous-board-Ultra-low/32827172081.html


Datasheet with the 42-byte LUT format used in the 4.2" display, but not the exact correct part.
https://www.smart-prototyping.com/image/data/9_Modules/EinkDisplay/GDEW0154T8/IL0373.pdf


Interesting thread with other folks experimenting with LUTs on the 2.7" display.
https://github.com/olikraus/u8g2/issues/318


Waveshare (distributor) datasheet
https://www.waveshare.com/w/upload/6/6a/4.2inch-e-paper-specification.pdf



Good Display (manufacturer) datasheet
http://www.good-display.com/products_detail/productId=321.html

Waveform "theory" with class 7-5-7 pulse sequence:
http://www.multicomponent.se/sub_group_files/13dae3f428be3929dc13fed1f79c5e40.pdf

My favorite microcontroller dev board, the Teensy: https://www.pjrc.com/teensy/

The new awesome 5-series oscilloscope from Tek: https://www.tek.com/oscilloscope/5-series-mso-mixed-signal-oscilloscope


Saturday, July 1, 2017

World's smallest lightbulb flasher? Flashing Light Prize 2017




I built an extremely small lightbulb flasher and describe the design process and challenges. This video is free for Patreon subscribers, and if I win the contest prize, I will donate the winnings to a STEM education charity.

2017 Flashing Light Prize: https://www.flashinglightprize.com/

Source of micro light bulbs: http://cir-kitconcepts.com/shop/

Single Schmitt inverter: https://www.digikey.com/product-detai...

The SR416 cell is the smallest primary power source available: http://www.watchbatteries-usa.com/siz...

Spot Welder: https://www.powerstream.com/spot-weld...

Big thanks to Tektronix for very useful test gear. Much appreciated!

Applied Science on Patreon: https://www.patreon.com/AppliedScience

Monday, May 29, 2017

Waterjet cutter built with a cheap pressure washer



Building an abrasive waterjet cutter with a $150 pressure washer.

Water orifice, mixing tube (nozzle), cutting head, high pressure fittings, valve: https://www.accustream.com/

80 grit garnet abrasive - ebay
eg http://www.ebay.com/itm/40-LBS-Garnet-80-grit-coarse-med-sand-blasting-abrasive-Fast-Cutting-Media-/272599344178

Sun Joe pressure washer: https://www.amazon.com/Joe-SPX3000-Pressure-14-5-Amp-Electric/dp/B00CPGMUXW

Pressure gauge - https://www.mcmaster.com/#4053K15

Good waterjet background and design info: https://wardjet.com/waterjet/university/nozzle-orifice

Good selection of higher-end pressure washers: https://www.pressurewashersdirect.com/

Wikipedia waterjet cutter (diagram image source): https://en.wikipedia.org/wiki/Water_jet_cutter


Support more Applied Science videos: https://www.patreon.com/AppliedScience

Thursday, March 23, 2017

T-shirts available now

Hello!  I have re-launched the Applied Science T-shirt campaign on Teepspring.  It will end in just a few days, but will re-launch after that, and be active for at least two weeks.  These shirts are being sold at-cost -- thanks so much for your support!

https://teespring.com/AppliedScience_youtube


Monday, February 20, 2017


 I show how to collect detailed CAN bus data from a Tesla Model S, and display it in the car's own web browser!

Complete Raspberry Pi with CAN bus shield and 12V buck converter: http://copperhilltech.com/raspberry-pi-3-system-with-can-bus-interface/

Tesla diagnostic connector: https://www.panjo.com/buy/tesla-diagnostic-cable-for-ms-mx-sept-2015-and-up-bare-wire-version-308125

RPi CAN bus tutorial: http://www.cowfishstudios.com/blog/canned-pi-part1

Get node.js installed on the RPi: http://thisdavej.com/beginners-guide-to-installing-node-js-on-a-raspberry-pi/

I used socket.io, which is a module that installs into node.js: https://www.npmjs.com/package/socket.io

Diagnostic connector pinout (scroll through the images):
http://store.evtv.me/proddetail.php?prod=TeslaCANKit





Tesla CAN bus reverse engineering: https://skie.net/skynet/downloads

Basic sequence to setup the server on the Pi:
sudo ip link set can0 type can bitrate 500000 listen-only on
sudo ip link set can0 up

candump -cae can0,0:0,#FFFFFFFF

candump -cae can0,0:0,#FFFFFFFF | grep 106 | awk -Winteractive '{ print $10}' | node app.js

I will post the node.js code on my blog:


Support Applied Science on Patreon:
https://www.patreon.com/AppliedScience


app.js:

var readline = require('readline');
var rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
  terminal: false
});
pipedata = '';
rl.on('line', function(line){
    console.log(line);
pipedata = line;
});

var http = require('http'),
    fs = require('fs'),
    // NEVER use a Sync function except at start-up!
    index = fs.readFileSync(__dirname + '/index.html');

// Send index.html to all requests
var app = http.createServer(function(req, res) {
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.end(index);
});

// Socket.io server listens to our app
var io = require('socket.io').listen(app);

// Send current time to all connected clients
function sendTime() {
//    io.emit('time', { time: new Date().toJSON() });
    io.emit('time', pipedata);
}

// Send current time every 10 secs
setInterval(sendTime, 100);

// Emit welcome message on connection
io.on('connection', function(socket) {
    // Use socket to communicate with this particular client only, sending it it's own id
    socket.emit('welcome', { message: 'Welcome!', id: socket.id });

    socket.on('i am client', console.log);
});

app.listen(8080);


index.html:


<!doctype html>

<html>

    <head>

        <script src='/socket.io/socket.io.js'></script>

        <script>

            var socket = io();



            socket.on('welcome', function(data) {

                addMessage(data.message);



                // Respond with a message including this clients' id sent from the server

                socket.emit('i am client', {data: 'foo!', id: data.id});

            });

            socket.on('time', function(data) {

                addMessage(data);

            });

            socket.on('error', console.error.bind(console));

            socket.on('message', console.log.bind(console));



            function addMessage(message) {

              //  var text = document.createTextNode(message);

                  document.getElementById('messages').textContent = message;

        //     el = document.createElement('li'),

               //     messages = document.getElementById('messages');



              //  el.appendChild(text);

              //  messages.appendChild(el);

            }

        </script>



<style>

p.sansserif { font-family: Arial, Helvtica, sans-serif; font-size:300%;}

</style>



    </head>

    <body>

        <p class = "sansserif" id='messages'>Hello</p>

    </body>

</html>