Differences

This shows you the differences between two versions of the page.

Link to this comparison view

--- en:iot-open:remotelab:itt:remotelights [2018/11/14 16:43] – rim.puks
+++ en:iot-open:remotelab:itt:remotelights [2020/07/20 09:00] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
-====== RGB LED module ======
+===== ITT RGB LED module =====
-Laboratory is located at the office of ITT Group in Tallinn, Estonia.
+This laboratory is located in the office of ITT Group in Tallinn, Estonia.
-Introduction
+==== Introduction  ====
-Here provide some general idea of the laboratory. Do not use very complicated phrases. It is to be understood by people with limited understanding of the technology. Photos, schematic and drawings may be attached as well. Write objectives for the laboratory i.e. “its purpose is to model ….” or “simulate”, or simply to “practice”. Write some objectives. Provide a link to the live video stream (if any).
+This laboratory consists of an RGB LED module connected to the ITT IoT controller module. The module contains one RGB LED. This node can be used to create very basic MQTT systems but can also be used as a signalling part of other more complicated systems.
-Prerequisites
+{{:en:iot_homelab_kit:hardware:led2.png?200 |}}
-Describe prerequisite readings, software, hardware (if any) - note - only those that apply to ALL scenarios, knowledge necessary to understand. I case single scenario requires some extra knowledge/prerequisites, provide it with scenario document, not here.
-Technical details
+==== Prerequisites ====
-Provide technical details on the construction of the laboratory, both hardware, and software. Use technical words and sentences. It is to be understood by technology-related people. Consider it as a kind of laboratory hardware and eventually software implementation. Sections below (remove section if not present) present details. Provide circuit, essential mechanical schema, if necessary to use the laboratory and understand its physics/mechanics, etc.
+General knowledge of MQTT protocol: topics, brokers, subscribe, publish.
-Sensors
+==== Technical details ====
-Describe sensors (if any). Provide details on measured values, connection details, accuracy, protocols, its relation to the physical/mechanical part of the laboratory (if any). Add photos and schematics, where the sensor is located. In case the sensor is virtual, do not expose it - present as physical until it is essential to know it regarding study (i.e. code implementation, timings, etc.). Provide links to external resources regarding i.e. necessary libraries, protocol definition, etc.
+This laboratory conisists of a ITT IoT controller module connected to a RGB LED module.
-Actuators
+=== Actuators ===
-Describe actuators, their impact on the physical/mechanical part of the laboratory device, limits, connections, etc. Add photos and schematics, where the actuator is located. In case actuator is virtual, do not expose it - present as physical until it is essential to know it regarding study (i.e. code implementation, timings, etc.). Provide links to external resources regarding i.e. necessary libraries, protocol definition, etc.
+This laboratory involves a WS2812B RGB LED. RGB LEDs are basically three LEDs (red, green, blue) that are built inside one shell. They include a WS2812 driver that makes it possible to use only one pin to control them.
-Software, libraries and externals
+=== Specifications ===
-Provide a list of software, software libraries and external resources (i.e. files) necessary during code development. Please note, write here only common for all hands-on-labs scenarios (there is a relevant section in scenario template. Remove this section if empty.
-Communication
+  * LED size: 5050
-Describe communication if it is implemented and sealed (not intended to be implemented by students, or provided i.e. as default code). Present data flow. Describe protocols and details i.e. key-value pairs, etc. Provide how exceptions are handled.
+  * Colors: 16777216
-Limits
+=== Electrical connection ===
-Provide information about limits on usage, i.e. need for maintenance/service break, access mode (parallel, booking, etc.), manual mechanical reset, etc.
-Hands-on labs
+Connected to port GPIO4.
-List study scenarios (hands-on labs), linking to the Dokuwiki pages with hands-on labs descriptions (there should be a separate page for each scenario). Classify each scenario and refer to the target group using starting keywords: * Beginners * Undergraduates * Masters * Professionals Note, assume that more professional group automatically contains less professional ones. Note - use language and as appropriate to the target group, i.e.:
+=== Software, libraries and externals ===
+To control WS2812B RGB LED the following libraries are used:
+  * ITTIoT libary - used to program the controller module.
+  * Adafruit NeoPixel libary - used to control the RGB LED.
+=== Communication ===
+The user can connect to this controller using the Distancelab environment.
+=== Limits ===
+At the same time, one user can program the controller. But all users connected to the Distancelab MQTT broker can control the RGB LED, assuming they use the topic described in the controller program.
+==== Hands-on labs ====
+=== Example code ===
+<code c>
+#include <Arduino.h>
+#include <ittiot.h>
+#include <Adafruit_NeoPixel.h>
+#define PIN            D2
+// When we setup the NeoPixel library, we tell it how many pixels,
+// and which pin to use to send signals.
+// Note that for older NeoPixel strips you might need to change
+// the third parameter--see the strandtest
+// example for more information on possible values.
+Adafruit_NeoPixel pixels = Adafruit_NeoPixel(1, PIN, NEO_GRB + NEO_KHZ800);
+// https://stackoverflow.com/questions/9072320/split-string-into-string-array
+String getValue(String data, char separator, int index)
+{
+  int found = 0;
+  int strIndex[] = {0, -1};
+  int maxIndex = data.length()-1;
+  for(int i=0; i<=maxIndex && found<=index; i++)
+  {
+    if(data.charAt(i)==separator || i==maxIndex)
+    {
+        found++;
+        strIndex[0] = strIndex[1]+1;
+        strIndex[1] = (i == maxIndex) ? i+1 : i;
+    }
+  }
+  return found>index ? data.substring(strIndex[0], strIndex[1]) : "";
+}
+// Change RGB LED color
+// mosquitto_pub -u test -P test -t "ITT/IOT/3/rgb" -m "51;255;153"
+void iot_received(String topic, String msg)
+{
+  Serial.print("MSG FROM USER callback, topic: ");
+  Serial.print(topic);
+  Serial.print(" payload: ");
+  Serial.println(msg);
+  String r = getValue(msg,';',0);
+  String g = getValue(msg,';',1);
+  String b = getValue(msg,';',2);
+  Serial.print("R: ");
+  Serial.println(r);
+  Serial.print("G: ");
+  Serial.println(g);
+  Serial.print("B: ");
+  Serial.println(b);
+  // Moderately bright green color.
+  pixels.setPixelColor(0, r.toInt(), g.toInt(), b.toInt());
+  pixels.show(); // This sends the updated pixel color to the hardware.
+}
+void iot_connected()
+{
+  Serial.println("MQTT connected callback");
+  iot.subscribe("rgb");
+  iot.log("IoT NeoPixel example!");
+}
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println("Booting");
+  iot.printConfig(); // print json config to serial
+  iot.setup();
+  pixels.begin(); // This initializes the NeoPixel library.
+}
+void loop()
+{
+  iot.handle();
+  delay(200);
+}
+</code>
+==== Support ====
+info@ittgroup.ee
-  * Beginners: Elementary operations on the Arduino 2x16 LCD screen.
-  * Undergraduates: Visualizing temperature and humidity on the remote screen.
-  * Masters: Using power saving states to limit power consumption.
-Support
-Give some information on how to access help, how to get support in case of the trouble etc.

en/iot-open/remotelab/itt/remotelights.1542213836.txt.gz · Last modified: 2020/07/20 09:00 (external edit)