Tag: Homewizard

Fun with ESP, WS2812 and Homewizard

Fun with ESP, WS2812 and Homewizard

Well, I managed to get the ESP8266 working with the WS2812 in the Arduino IDE and it is time for some fun in combination with my Homewizard.

What I wanted to accomplish is this: I have solar panels at home and I have connected these to my Homewizard (a domotica appliance) along with the power meters which means my Homewizard knows about my power usage and my solar power production. What I wanted to do is have a small WS2812 ring show my usage and my production simultaneously. I defined usage as being the ‘red’ color and solar production as ‘yellow’. I want to show the production at the same time as the usage so I thought I would define each led to be the equivalent of 250 W power. I would ‘plot’ both the production and the usage on the circle starting at the same point. The overlap would be orange and excess solar power would be yellow and excess usage would be red, so if the circle showed 3 orange leds and 3 yellow, it meant I was producing 1500W (3+3 times 250W) while at the same time using 750W (3 times 250W). If the circle would show 3 orange and 3 red, it would mean 750W production and 1500W usage. After attempt 1 I found out that it was possible to use more than the LEDs would allow (ok, has not happened yet, but theoratically it is possible so I decided to add overflow. If production or usage would be over 3000W (12 times 250W), any excess would result in blue leds at the beginning, symbolizing double ‘value’ LEDs.

Still with me so far? After implementing, I found out that during Autumn, which is now when I created this project, production is not that high and my usage is usually also not that high, so often only 2 or 3 LEDs would light up. What I needed was increased resolution in such cases. I know, way too complex but he, it was meant to be a fun project. So I introduced green LEDs at the beginning. One green LED meant the resolution of the remaining 11 LEDs was 125W and two green LEDs mean the resolution of the remaining 10 LEDs was 50W.

The code will probably not be something you want to use without modifying but it might help you get some ideas on how to play with the WS2812. The code for getting the solar production and usage might be useful to others with a Homewizard.

github-mark-32px Available on GitHub with more comment in the code. Direct download.

Let’s look at the code:

#include <Adafruit_NeoPixel.h>
#include <ESP8266WiFi.h>
#include <PAM_WiFiConnect.h>
#include <PAM_WiFiClient.h>

#define CIRCLEPIN 2
#define PIXELCOUNT 12
#define POWERPERLED1 250
#define POWERPERLED2 125
#define POWERPERLED3 50

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(PIXELCOUNT,CIRCLEPIN,

int solarPower = 0;
int powerConsumption = 0;
float solarPowerDay = 0;
float powerConsumptionDay = 0;

void setup() {
  for(byte i=0;i<PIXELCOUNT;i++){
    pixels.setPixelColor(i, pixels.Color(0,0,0));

void readSolar () {
  String t = getURL("YourHomewizardUrl","/YourHWPassword/get-status",80);
  t = t.substring(t.indexOf("energylinks"));
  t = t.substring(t.indexOf("s1"));
  t = t.substring(t.indexOf("po")+4);
  int xsolarPower = t.substring(0,t.indexOf(",")).toInt();
  t = t.substring(t.indexOf("dayTotal")+10);
  int xsolarPowerDay = t.substring(0,t.indexOf(",")).toFloat()*1000;
  t = t.substring(t.indexOf("used"));
  t = t.substring(t.indexOf("po")+4);
  int xpowerConsumption = t.substring(0,t.indexOf(",")).toInt();
  t = t.substring(t.indexOf("dayTotal")+10);
  int xpowerConsumptionDay = t.substring(0,t.indexOf(",")).toFloat()*1000;
  t = t.substring(0,t.indexOf("heatlinks"));
  Serial.print("Solar       now :");
  Serial.print("Consumption now :");
  Serial.print("Solar       day :");
  Serial.print("Consumption day :");
  if (xsolarPower!=0 || xpowerConsumption!=0) {
    solarPower = xsolarPower;
    solarPowerDay = xsolarPowerDay;
    powerConsumption = xpowerConsumption;
    powerConsumptionDay = xpowerConsumptionDay;

void loop() {

  byte solarLed;
  byte powerLed;
  byte base;
  if (_max(solarPower,powerConsumption)<=POWERPERLED3*(PIXELCOUNT-2)) {
    solarLed = round((solarPower+POWERPERLED3/2)/POWERPERLED3)+4;
    powerLed = round((powerConsumption+POWERPERLED3/2)/POWERPERLED3)+4;
    base = 2;
    for (byte i=0;i<base;i++) {
  } else if (_max(solarPower,powerConsumption)<=POWERPERLED2*(PIXELCOUNT-1)) {
    solarLed = round((solarPower+POWERPERLED2/2)/POWERPERLED2)+2;
    powerLed = round((powerConsumption+POWERPERLED2/2)/POWERPERLED2)+2;
    base = 1;
  } else {
    solarLed = round((solarPower+POWERPERLED1/2)/POWERPERLED1);
    powerLed = round((powerConsumption+POWERPERLED1/2)/POWERPERLED1);
    base = 0;
    if (solarLed>PIXELCOUNT || powerLed>PIXELCOUNT) {
      base = _max(solarLed,powerLed)-PIXELCOUNT;
      for (byte i=0;i<base;i++) {
  for (byte i=base;i<_min(solarLed,powerLed)-base;i++) {
  if (powerLed>solarLed) {
    for (byte i=_max(base,_min(solarLed,powerLed)-base);i<powerLed-base;i++) {
    for (byte i=powerLed-base;i<PIXELCOUNT;i++) {
  } else {
    for (byte i=_max(base,_min(solarLed,powerLed)-base);i<solarLed-base;i++) {
    for (byte i=solarLed-base;i<PIXELCOUNT;i++) {

Ok, maybe way to much code to just dump here but it’s not that difficult to read.

Let’s start with the includes; NeoPixel library from AdaFruit, the standard ESP8266WiFi library and my own two libraries, PAM_WiFiConnect and PAM_WiFiClient. Next we define our constants and initalize the NeoPixel library.

The setup function is straight forward, set up Serial, connect to wifi and set all pixels to black.

The readSolar function connects to the Homewizard and gets the status information. This json file is than parsed a couple of times to get the current solar power production in solarPower, the days solar power production solarPowerDay, the current power consumption, powerConsumption and finally the power consumption of the day, powerConsumptionDay. Both day values are not used in this sketch. I intend to make some kind of switches where you can choose to see the current production/consumption or the totals of the day.

The loop function is where the number of leds and color is determined. The first section, the extensive if statement, determines which value to assign to each led, 250W, 125W or 5oW. This is done by checking the maximum of the values of solarPower and powerConsumption. If the maximum is small enough to fit within the 50W scale that is used, if not it is checked whether it will fit in the 125W scale and else it will be put in the 250W scale. If it is 50W, the first 2 leds are made green (signifying a change from the default scale) and 125W shows 1 green led.

Next the color of the remaining leds is determined by checking the maximum (to see if blue leds are needed) and than counting how many should be red (power usage), yellow (power production) or orange (production and usage).

As mentioned before, you probably cannot use the supplied code straight ‘out of the box’ but you can use it for ideas.

The end result of my solar meter in a small plastic box:


At the bottom left, a USB to serial adapter. In the bottom middle a ESP-12E on a small breakout board. At the middle left a reed contact which allows for an update to the code by holding a magnet near the back of the box and finally the 12 bit neopixel circle.

When the box is closed, there is a normal piece of paper at the top abive the lights so that they are not too bright and slightly diffused which gives this end result:


Homewizard API, basic switches & scenes

Homewizard API, basic switches & scenes


I briefly wrote on how you can use the Homewizard to turn on and off any lights you created with the ESP8266 (like my ESPöcka) but the Homewizard also has an API of it’s own that you can use to control all devices attached to your Homewizard.

The API is undocumented, at least officially. There are others out there who have written about it. I will attempt something similar but with a focus on more detailed instructions.

This is part 1 which will cover the simple basics.

The homewizard API works purely on HTTP GET commands which means you can type any of them directly in your browser. Every command you send is answered by a reply. This reply is in JSON format (there is plenty of information on JSON on the internet link 1, link 2, so I won’t go in detail here). If you only care about switching things on and off, you don’t even have to understand the reply, the basic fire-and-forget method.

Each API call is formatted similarly. All of them start with:


Yes, unfortunately the password you use for the homewizard is send as part of the url which means that anyone who has access to your browse history or your proxy (if you use one) can control your lights and other equipment attached to your Homewizard. The Homewizard app uses the same API, so if you are using that, the password will have been send in clear text anyway.

After the base URL (which I will symbolize with * in the examples), you can add the commands. There are high level 2 types of commands, informational and controlling.

Informational API calls

With informational requests, the answer of course matters. Since the reply is in JSON (which is nothing else than text with strict rules on formatting), you will need to understand a little how to read it, to understand the answers. It also helps to have some sort of JSON viewer. I use Firefox and I have installed this plugin to help view the JSON or copy the answer you receive in this online formatter.


All devices connected to your Homewizard are referred to as sensors. To get a list of all sensors (which include groups) you send the following command:


And you will get a reply similar to this (I have cut out sections which are not relevant now):

      "time":"2016-04-01 09:24",
            "name":"Name 1",
            "name":"Name 2",
            "name":"Name 3",

(I have used the online formatter to get the text like this).

In part 1, I will only focus on switches and scenes. In the response above, we are interested in the section after response and (for part 1) in particular the sections switches and scenes. As you can see, in each section you get a list of sensors of that type. So in the example above there are 3 switches, Name 1, 2 and 3 which are currently all off. Name 1 is a normal switch, Name 2 is a dimmer switch which is currently set at dim level 0 and Name 3 is an IP switch (virtual). There is one scene defined which is called Living. A scene is a group of switches which you can control with one call/click/switch.

Controlling API calls

Now that you have the id’s for the switches and scenes, you can control them. The id’s will remain the same as long as you don’t remove any of the switches/scenes before that id. So for proper programming, you should do a */get-sensors and look for the switch you want using the name, get the id and than use that id for switching. The url for switching a switch on is:


where <id> is the number of the id in the */get-sensors list, so for example */sw/1/on. Switching a scene is the same except that you need to change the sw into gp.

The url for switching a scene off is:


where <id> is the number of the id in the */get-sensors list. Switching a switch off is the same except that you need to change the gp into sw.

To change the dimlevel of a switch you use the url:


where again <id> is the number of the id in the */get-sensors list and <dimlevel> is a number between 0 and 100 (inclusive) where 0 means totally off and 100 means fully on. You can switch dimmer switches on and off without using the dim command, assuming that your device remembers it’s last dim level (the COCO devices do).

Remember that you can do a fire-and-forget, so you can do a request to the URL and not even listen to the answer. Needless to say, it will mean if you change the password or change the id and you don’t do error checking, either nothing will happen or unexplained things will happen. In my ESP8266 projects, for now, I do an API call without checking for the answer. In the near future I might set up a proxy server which can log if there is an error.

That’s it for basic switches and scenes. Check here for more pages on the Homewizard.

ESP8266 and Homewizard

ESP8266 and Homewizard

As you may have seen in my meet ESPöcka article, I have created a led light with an ESP8266 inside. I’ve setup the ESP with a webserver that allows me to turn on the lights (in different colors) through an API call. I plan to build more of these (with normal led strips) and wouldn’t it be great if these can be controlled via normal switches.

In my house I also have a homewizard which is basically a gateway to my different COCO switches, temperature and other sensors. It comes with it’s own smartphone app but more importantly, it run a webserver with an API and it allows you to control IP switches which is what my ESPöcka is.

Setting up an IP switch (more on the API in a different article) is easy. Through the interface on the app, you select the menu (top left) and click on Manage Devices.
Than select Add Device, followed by Switches & lights
followed by IP switch.
Give it a name
and save it after which you will be prompted with an On URL and an Off URL.

The URLs you give can be local (to the homewizard) URLs because your homewizard device does the call so there is no need to allow internet access to your lights.
As you can see, there are many options, HTTP GET, HTTP POST, a UDP or a TCP call and even Wake on LAN. For my ESPöcka, I have used a HTTP GET call with parameters to turn it on in red or turn it off. It works.