{"id":1405,"date":"2016-12-18T16:52:31","date_gmt":"2016-12-18T16:52:31","guid":{"rendered":"http:\/\/fbcs.co.uk\/?p=1405"},"modified":"2017-12-11T18:26:49","modified_gmt":"2017-12-11T18:26:49","slug":"cheerlights-2016","status":"publish","type":"post","link":"https:\/\/wp.fbcs.co.uk\/cheerlights-2016\/","title":{"rendered":"Cheerlights 2016"},"content":{"rendered":"<p><script type=\"text\/javascript\" src=\"\/wp-content\/themes\/fbcs2012\/js\/mqttws31.js\"><\/script><br \/>\n<script type=\"text\/javascript\" src=\"\/wp-content\/themes\/fbcs2012\/js\/mqtt_cheerlights.js\"><\/script><a href=\"http:\/\/cheerlights.com\/build\/\" target=\"_blank\" rel=\"noopener\">Cheerlights<\/a> is a project that synchronises the colours of internet-connected devices around the world.\u00a0 Anyone can choose the current colour simply by sending a Tweet that includes the word &#8216;cheerlights&#8217; and the name of a colour (one of <span style=\"color: #ff0000;\">red<\/span>, <span style=\"color: #008000;\">green<\/span>, <span style=\"color: #0000ff;\">blue<\/span>, <span style=\"color: #00ffff;\">cyan<\/span>, <span style=\"background-color: #000000; color: #ffffff;\">white<\/span>, <span style=\"background-color: #000000; color: #fdf5e6;\">oldlace \/ warmwhite<\/span>, <span style=\"color: #800080;\">purple<\/span>, <span style=\"color: #ff00ff;\">magenta<\/span>, <span style=\"color: #ffff00;\">yellow<\/span>, <span style=\"color: #ffa500;\">orange<\/span>, <span style=\"color: #ffc0cb;\">pink<\/span>, or <span style=\"color: #000000;\">black<\/span>).<\/p>\n<p>The current colour is <span id=\"fbcsmqttname\"><\/span>:<\/p>\n<div id=\"fbcsmqtt\" style=\"display: inline-block; width: 100%; height: 2em;\"><\/div>\n<p>The <a href=\"http:\/\/cheerlights.com\/\" target=\"_blank\" rel=\"noopener\">Cheerlights website<\/a> has all the information about how to get involved, with lots of examples of projects to inspire you.<\/p>\n<p>So here&#8217;s another one.\u00a0 Nothing radically original: the hardware is adapted from various sources, although the software is largely my own.\u00a0 When no new colours come through for a while, it displays a randomly changing hue.<\/p>\n<p>It&#8217;s currently installed in our kitchen, as mentioned in a <a href=\"https:\/\/twitter.com\/ChrisGDennis\/status\/807553706342367232\" target=\"_blank\" rel=\"noopener\">recent Tweet<\/a>.<\/p>\n<h2>Hardware<\/h2>\n<p>The heart of the gadget is the <a href=\"https:\/\/en.wikipedia.org\/wiki\/ESP8266\" target=\"_blank\" rel=\"noopener\">ESP8266<\/a> chip, which can run quite sophisticated code and has built-in WiFi connectivity.<\/p>\n<div id=\"attachment_1429\" style=\"width: 310px\" class=\"wp-caption alignright\"><a href=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu.png\"><img aria-describedby=\"caption-attachment-1429\" loading=\"lazy\" class=\"wp-image-1429 size-medium\" src=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu-300x241.png\" width=\"300\" height=\"241\" srcset=\"https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu-300x241.png 300w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu-768x616.png 768w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu-1024x821.png 1024w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu-624x500.png 624w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-nodemcu.png 1200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-1429\" class=\"wp-caption-text\">ESP8266-12E packaged as a NodeMCU board on the Lolin power supply and breakout base<\/p><\/div>\n<p>For convenience, I used the ESP8266 packaged as a <a href=\"http:\/\/frightanic.com\/iot\/comparison-of-esp8266-nodemcu-development-boards\/#v2\" target=\"_blank\" rel=\"noopener\">NodeMCU Devkit ESP8266-12E<\/a>, and plugged that into a Lolin NodeMCU Base Shield.\u00a0 The base allows me to plug in a single 12V supply that provides power for both the NodeMCU board and the LED strip.<\/p>\n<h3>LED strip<\/h3>\n<p>I used a cheap strip of RGB LEDs [&#8230; need the specs &#8212; current drawn etc.] &#8212; <strong>not<\/strong> the clever WS2811 \/ &#8216;Neopixel&#8217; ones.\u00a0 The only issue with them is that the colours aren&#8217;t balanced: for example, mixing maximum red and maximum green (to get yellow) gives a nasty shade of yellow-green.\u00a0 I had to add some factors in the code to allow for this.<\/p>\n<h3>Interface board<\/h3>\n<p>The home-made bit of the hardware converts the PWM (see below) signals to the voltages required by the LED strip.<\/p>\n<p><a href=\"https:\/\/forum.arduino.cc\/index.php?topic=114705.0\"><img loading=\"lazy\" class=\"alignright size-medium wp-image-1523\" src=\"https:\/\/fbcs.co.uk\/wp-content\/uploads\/mosfet-pwm-300x254.png\" alt=\"\" width=\"300\" height=\"254\" srcset=\"https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/mosfet-pwm-300x254.png 300w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/mosfet-pwm-624x528.png 624w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/mosfet-pwm.png 676w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a>The circuit I ended up with is derived from\u00a0<a href=\"https:\/\/forum.arduino.cc\/index.php?topic=114705.msg863357#msg863357\" target=\"_blank\" rel=\"noopener\">https:\/\/forum.arduino.cc\/index.php?topic=114705<\/a>.<\/p>\n<p><span style=\"background-color: #ffff00;\"><strong>Please note<\/strong><\/span> that I don&#8217;t really know what I&#8217;m doing with electronics: if you make use of this design, you must do your own checks and testing to make sure that the circuit doesn&#8217;t draw too much current or overheat.<\/p>\n<p>It uses three IRL520N MOSFETs, one to control the 12V supply to each colour, as driven\u00a0by the signals from the ESP8266.<\/p>\n<div id=\"attachment_1431\" style=\"width: 310px\" class=\"wp-caption alignright\"><a href=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights2016_bb.png\"><img aria-describedby=\"caption-attachment-1431\" loading=\"lazy\" class=\"wp-image-1431 size-medium\" src=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights2016_bb-300x123.png\" width=\"300\" height=\"123\" srcset=\"https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights2016_bb-300x123.png 300w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights2016_bb-768x315.png 768w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights2016_bb-1024x419.png 1024w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights2016_bb-624x256.png 624w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-1431\" class=\"wp-caption-text\">Breadboard layout for the MOSFETs<\/p><\/div>\n<p>The circuit layout, as a breadboard design created in Fritzing is shown. \u00a0The .FZZ file can also be <a href=\"\/wp-content\/uploads\/images\/cheerlights2016.fzz\">downloaded<\/a>.<\/p>\n<div id=\"attachment_1430\" style=\"width: 310px\" class=\"wp-caption alignright\"><a href=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1.png\"><img aria-describedby=\"caption-attachment-1430\" loading=\"lazy\" class=\"size-medium wp-image-1430\" src=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1-300x223.png\" alt=\"\" width=\"300\" height=\"223\" srcset=\"https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1-300x223.png 300w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1-768x570.png 768w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1-1024x759.png 1024w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1-624x463.png 624w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-and-leds-1.png 1200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-1430\" class=\"wp-caption-text\">NodeMCU, interface board, and LED strip.\u00a0 (This shows a strip with separate red, green, and blue LEDs; I later used a better strip with proper three-colour LEDs)<\/p><\/div>\n<p>I transferred the MOSFETs and resistors to stripboard to make it more permanent.<\/p>\n<div id=\"attachment_1426\" style=\"width: 310px\" class=\"wp-caption alignright\"><a href=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits.png\"><img aria-describedby=\"caption-attachment-1426\" loading=\"lazy\" class=\"size-medium wp-image-1426\" src=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-300x174.png\" alt=\"\" width=\"300\" height=\"174\" srcset=\"https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-300x174.png 300w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-768x446.png 768w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-1024x595.png 1024w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits-624x362.png 624w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-circuits.png 1200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-1426\" class=\"wp-caption-text\">Close-up of the NodeMCU and interface board<\/p><\/div>\n<p>The circuits are mounted in a cardboard box, and held in place with Blu-Tack (other brands of sticky stuff are available).<\/p>\n<h2>Software<\/h2>\n<p>The hardware runs the NodeMCU firmware, which is <a href=\"https:\/\/nodemcu.readthedocs.io\/en\/master\/\" target=\"_blank\" rel=\"noopener\">thoroughly documented<\/a>, and provides a Lua interpreter\/compiler and filesystem.<\/p>\n<p>The NodeMCU was supplied with version 0.9.6 of the NodeMCU firmware, which was fine until I need to use the &#8216;http&#8217; module.\u00a0 For that, I downloaded a custom-built version of the latest firmware from the excellent service at <a href=\"https:\/\/nodemcu-build.com\/index.php\" target=\"_blank\" rel=\"noopener\">nodemcu-build.com<\/a>.\u00a0 My build included just the Lua modules that I needed, freeing up valuable space on the hardware. \u00a0The firmware\u00a0identifies itself as<\/p>\n<pre>NodeMCU custom build by frightanic.com\r\n branch: master\r\n commit: 81ec3665cb5fe68eb8596612485cc206b65659c9\r\n SSL: false\r\n modules: file,gpio,http,mqtt,net,node,pwm,tmr,uart,wifi\r\n build built on: 2016-12-09 18:27\r\n powered by Lua 5.1.4 on SDK 1.5.4.1(39cb9a32)<\/pre>\n<p>I found that I needed to erase the firmware before trying to upload a new one. \u00a0I used <a href=\"https:\/\/github.com\/espressif\/esptool.git\" target=\"_blank\" rel=\"noopener\">esptool.py<\/a> and these commands (adjusting the serial port and firmware filename to suit):<\/p>\n<pre>esptool.py --port \/dev\/ttyUSB0 erase_flash\r\nesptool.py --port \/dev\/ttyUSB0 write_flash -fm dio 0x00000 \"nodemcu-master-10-modules-2016-12-09-18-27-52-integer.bin\" --verify<\/pre>\n<p>The board has a micro-B USB socket which can be connected directly to your computer, and provides power as well as the connection for flashing firmware and uploading your own Lua code.<\/p>\n<p>The software that gets the colours from Cheerlights and sends them to the LEDs is on <a href=\"https:\/\/github.com\/StarsoftAnalysis\/Cheerlights2016\">Github<\/a>.<\/p>\n<p>I used the\u00a0<a href=\"https:\/\/esp8266.ru\/esplorer\/\" target=\"_blank\" rel=\"noopener\">ESPlorer<\/a> IDE to upload and run the Lua code.<\/p>\n<p>You will need to rename the file <code>wifi-ssids.example.lua<\/code> to <code>wifi-ssids.lua<\/code>, and then edit it to include your own SSID(s) and password(s).<\/p>\n<p>Once you&#8217;ve got it all running, you can rename <code>test.lua<\/code> to <code>init.lua<\/code> so that the code will run automatically when the circuit is powered up.<\/p>\n<p>It&#8217;s a bit quirky. \u00a0At one stage I seemed to be getting an unreliable feed via <a href=\"https:\/\/thingspeak.com\/channels\/1417\" target=\"_blank\" rel=\"noopener\">MQTT<\/a>, so I added code to use the <a href=\"http:\/\/cheerlights.com\/cheerlights-api\/\" target=\"_blank\" rel=\"noopener\">HTTP API<\/a> instead. \u00a0Now it uses both feeds, just to be sure. \u00a0As a result, it would be very easy to add another &#8216;colour source&#8217;, such as a temperature sensor, to control the colours.<\/p>\n<h3>Features \/ Bugs<\/h3>\n<ul>\n<li>To keep the light level fairly constant, each colour is scaled so that R+G+B is the same. \u00a0This means that the difference between <span style=\"color: #800080;\">purple<\/span>, and\u00a0<span style=\"color: #ff00ff;\">magenta<\/span> is lost.<\/li>\n<li><\/li>\n<\/ul>\n<h2>Installation<\/h2>\n<p>&#8216;Installation&#8217; is probably too strong a word. \u00a0I just stuck the LED strip along the shelf above the kitchen cupboards, tucked the hardware in amongst the crockery, and plugged the power supply into the socket that usually powers the extractor fan.<\/p>\n<p>Here&#8217;s the final result &#8212; making our new kitchen look very cheery.<a href=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue.png\"><img loading=\"lazy\" class=\"size-medium wp-image-1428 aligncenter\" src=\"http:\/\/fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue-300x200.png\" alt=\"\" width=\"300\" height=\"200\" srcset=\"https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue-300x200.png 300w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue-768x512.png 768w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue-1024x683.png 1024w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue-624x416.png 624w, https:\/\/wp.fbcs.co.uk\/wp-content\/uploads\/images\/cheerlights-2016-kitchen-blue.png 1200w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<h2>Issues<\/h2>\n<ul>\n<li>The software PWM sometimes seems to cause flickering. \u00a0Using dedicated chips for the PWM might help.<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Cheerlights is a project that synchronises the colours of internet-connected devices around the world.\u00a0 Anyone can choose the current colour simply by sending a Tweet that includes the word &#8216;cheerlights&#8217; and the name of a colour (one of red, green, blue, cyan, white, oldlace \/ warmwhite, purple, magenta, yellow, orange, pink, or black). The current [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[13,63,65],"tags":[],"_links":{"self":[{"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/posts\/1405"}],"collection":[{"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/comments?post=1405"}],"version-history":[{"count":56,"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/posts\/1405\/revisions"}],"predecessor-version":[{"id":1542,"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/posts\/1405\/revisions\/1542"}],"wp:attachment":[{"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/media?parent=1405"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/categories?post=1405"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.fbcs.co.uk\/wp-json\/wp\/v2\/tags?post=1405"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}