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-rw-r--r--assignments/blink-a-led/blink-a-led.md26
-rw-r--r--assignments/blink-a-led/blink-a-led.pdfbin722602 -> 731445 bytes
-rw-r--r--assignments/mqtt-with-button/mqtt-with-button.md50
-rw-r--r--assignments/mqtt-with-button/mqtt-with-button.pdfbin841066 -> 857213 bytes
-rw-r--r--slides/connected-arduino-slides.pdfbin293791 -> 287191 bytes
-rw-r--r--slides/connected-arduino-text.pdfbin298798 -> 287028 bytes
-rw-r--r--slides/connected-arduino.md449
-rw-r--r--slides/toc.md43
8 files changed, 220 insertions, 348 deletions
diff --git a/assignments/blink-a-led/blink-a-led.md b/assignments/blink-a-led/blink-a-led.md
index a08bc4e..72bbb9c 100644
--- a/assignments/blink-a-led/blink-a-led.md
+++ b/assignments/blink-a-led/blink-a-led.md
@@ -6,10 +6,19 @@ Check that your local environment is working properly.
## Configure the Arduino IDE
-Under *Tools* -> *Board* make sure that "NodeMCU 1.0 (ESP-12E Module)"
-is available and selected.
+1. Make sure the "ESP8266" core is installed. If it is not installed
+ follow the installation instructions:
-Create a new sketch with *File* -> *New* and compile it with *ctrl-R*.
+ [https://github.com/esp8266/Arduino#installing-with-boards-manager](https://github.com/esp8266/Arduino#installing-with-boards-manager)
+
+1. Under *Tools* -> *Board* make sure that "NodeMCU 1.0 (ESP-12E
+ Module)" is available and selected.
+
+1. Select the correct serial port: *Tools -> Port*.
+
+1. Select the highest upload speed: *Tools -> Upload Speed*.
+
+1. Create a new sketch with *File* -> *New* and compile it with *ctrl-R*.
## Step 1
@@ -24,7 +33,7 @@ orientation is not important, but the LED's orientation is important.
## Step 2
-Implement `setup()` and `loop()`. In `setup()` configure the LED pin and blink the LED in `loop()`.
+Implement `setup()` and `loop()`: In `setup()` configure the LED pin and blink the LED in `loop()`.
Use these functions:
@@ -32,9 +41,14 @@ Use these functions:
Serial.begin(115200);
Serial.println(string);
+// Pin is D1/D2/D..
+// mode is INPUT or OUTPUT
pinMode(pin, mode);
-digitalWrite(pin, state); // HIGH or LOW
-delay();
+
+// HIGH or LOW
+digitalWrite(pin, state);
+
+delay(ms);
~~~
## Tips
diff --git a/assignments/blink-a-led/blink-a-led.pdf b/assignments/blink-a-led/blink-a-led.pdf
index da370c4..655f964 100644
--- a/assignments/blink-a-led/blink-a-led.pdf
+++ b/assignments/blink-a-led/blink-a-led.pdf
Binary files differ
diff --git a/assignments/mqtt-with-button/mqtt-with-button.md b/assignments/mqtt-with-button/mqtt-with-button.md
index c825615..30defc8 100644
--- a/assignments/mqtt-with-button/mqtt-with-button.md
+++ b/assignments/mqtt-with-button/mqtt-with-button.md
@@ -6,6 +6,11 @@
* Publish a message when a button is pressed.
* Subscribe to a topic to control the LED
+## Preparation
+
+* Install the *PubSubClient* library. Use the library manager under
+ *Sketch -> Include library -> Library Manager* to install it.
+
## Step 1
Wire up this schematic on the bread board:
@@ -16,10 +21,8 @@ Wire up this schematic on the bread board:
# Step 2
-* Tip: change upload speed to max.
-
-* Read button in `loop()`. If the button's state changes, print a
- message.
+* Read button's value inside `loop()`. If the button's state changes,
+ print a message.
*Note:* reading the button in a busy loop is not really a best
practice as it uses lots of energy. Instead use the `attachInterrupt`.
@@ -29,34 +32,35 @@ practice as it uses lots of energy. Instead use the `attachInterrupt`.
* Connect to the Wi-Fi network
* Connect to MQTT broker
+See the slides for example code.
+
# Step 4
-* Publish a message on button press on the topic
+* Create a subscription for `ndc/$device-id/#` with HiveMQ's web ui:
+ http://www.hivemq.com/demos/websocket-client/
+* Publish a message when the button is pressed on the topic
`ndc/$device-id/button`
# Step 5 (Bonus)
-Subscripe to a topic and do something with the led.
-
-* Subscribe to the topic you're publishing to.
-
-* Subscribe to the topic `ndc/$device-id/led`.
-
-* Use the value to for example turn the LED on/off, or change the
- LED's blinking pattern.
+*Feel free to be creative here.*
-## Tips
+The other useful half of MQTT is subscribing to topics and reacting to
+messages. Here are some example things you can do:
-To generate a client id make something with `ESP.getChipId()`{.cpp}
+* Subscribe to the topic you're publishing to and change the state of
+ the LED when the button is pressed. This will give you a very
+ complicated and brittle way of toggling a LED.
-Creating a `String` from a number:
+* In `loop` blink the led. Subscribe to another topic (for example
+ `ndc/$device-id/frequency`), and use the value as a way to control
+ the blink rate.
-* `String(123) => "123"`{.cpp}
-* Hex formatted: `String(0x123abc, HEX) => "123abc"`{.cpp}
+# Step 6 (Strech goal)
-Some APIs require "plain C strings" aka a `char *`{.cpp}. They can be
-converted with `String::c_str()`:
+Use a last will message to indicate if the device is online or not.
-~~~.c++
-char *cStr = myString.c_str();
-~~~
+* When connecting, include a last will message with topic
+ `ndc/$device-id/online` and payload `0`.
+* After a successfull connection, publish a similar message with the
+ payload `1`. Observe what happens when you unplug the device.
diff --git a/assignments/mqtt-with-button/mqtt-with-button.pdf b/assignments/mqtt-with-button/mqtt-with-button.pdf
index 8fcccf7..ccb511e 100644
--- a/assignments/mqtt-with-button/mqtt-with-button.pdf
+++ b/assignments/mqtt-with-button/mqtt-with-button.pdf
Binary files differ
diff --git a/slides/connected-arduino-slides.pdf b/slides/connected-arduino-slides.pdf
index cc258eb..7849f9a 100644
--- a/slides/connected-arduino-slides.pdf
+++ b/slides/connected-arduino-slides.pdf
Binary files differ
diff --git a/slides/connected-arduino-text.pdf b/slides/connected-arduino-text.pdf
index 6882209..3ad5987 100644
--- a/slides/connected-arduino-text.pdf
+++ b/slides/connected-arduino-text.pdf
Binary files differ
diff --git a/slides/connected-arduino.md b/slides/connected-arduino.md
index 16f93d4..512f8cb 100644
--- a/slides/connected-arduino.md
+++ b/slides/connected-arduino.md
@@ -16,167 +16,10 @@ header-includes:
---
-# NodeMCU
-
-!comment(aka NodeMCU aka ESP-12)
-
-## NodeMCU hardware
-
-!ifndef(QUICK)(
-![](images/NodeMCU-–-Board-de-desarrollo-con-módulo-ESP8266-WiFi-y-Lua-4.jpg)
-)
-
-## NodeMCU hardware
-
-!ifndef(QUICK)(
-\begin{center}
-!include(images/nodemcu.pgf)
-\end{center}
-)
-
-## ESP8266 software layers
-
-!ifndef(QUICK)(
-\begin{center}
-!include(images/esp+arduino-sdks.pgf)
-\end{center}
-)
-
-## ESP8266 + Arduino
-
-* Standard Arduino IDE
-* ESP8266 Arduino core
- * https://github.com/esp8266/Arduino
-
-## Arduino IDE
-
-!ifndef(QUICK)(
-![](images/arduino-ide.png)
-)
-
-## Arduino code structure
-
-~~~ .c++
-void setup() {
- // Called once
-}
-
-void loop() {
- // Called repeatedly
-}
-~~~
-
-::: notes
-
-MCU programming is often structured into:
-
-* Configure
- * CPU
- * GPIO ports
- * MCU's peripherals
- * The rest of the board
- * Configure application and callbacks.
-* Sleep
-
-Arduino chooses to run the cpu at 100% instead of the sleep step..
-
-:::
-
-## Arduino file structure
-
- foo/
- foo.ino
- config.h
-
-::: notes
-
-`foo.ino` must always be in a `foo` directory.
-
-config.h is created by "new tab".
-
-:::
-
-## Generic Arduino APIs
-
-~~~c++
-// Pin: D0, D1, etc.
-// Mode: OUTPUT, INPUT, INPUT_PULLUP
-void pinMode(uint8_t pin, uint8_t mode);
-
-// State: HIGH, LOW, true/false, 1/0
-void digitalWrite(uint8_t pin, uint8_t state);
-int digitalRead(uint8_t pin);
-
-unsigned long now millis();
-unsigned long now micros();
-~~~
-
-## ESP Arduino APIs
-
-~~~c++
-class {
- void restart();
- uint32_t getFreeHeap();
- uint32_t getChipId();
-
- ...
-} ESP;
-
-// Usage
-ESP.restart();
-~~~
-
-## ESP
-
-~~~c++
-// Top of file
-#include <ESP8266WiFi.h>
-
-// In setup()
-WiFi.mode(WIFI_STA);
-WiFi.begin(ssid, password);
-
-while (WiFi.status() != WL_CONNECTED) {
- delay(500);
- Serial.print(".");
-}
-
-Serial.println("");
-Serial.println("WiFi connected");
-Serial.println("IP address: ");
-Serial.println(WiFi.localIP());
-~~~
-
-## ESP Arduino APIs
-
-~~~c++
-class {
- String macAddress();
-
- wl_status_t status();
- int32_t RSSI();
-
- IPAddress localIP();
- IPAddress subnetMask();
- IPAddress gatewayIP();
- IPAddress dnsIP(uint8_t dns_no = 0);
-
- ...
-} WiFi;
-
-// Usage:
-
-Serial.println(WiFi.localIP().toString());
-~~~
-
-::: notes
-
-http://arduino-esp8266.readthedocs.io/en/latest/libraries.html
-
-:::
-
# What is IoT
+!comment
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
## What is IoT
* Not "a computer connected to the internet"
@@ -205,6 +48,7 @@ As for their definition.
What differentiates a computer from an IoT device?
:::
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
## What is an IoT Device?
@@ -214,12 +58,17 @@ What differentiates a computer from an IoT device?
* Network bandwidth and/or latency
* Storage
* Has connectivity
+
+!comment
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+* Has connectivity
* Bluetooth
* Wi-Fi
* NB-IoT
* LTE Cat-M
* LoRa
* Proprietary radio
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
::: notes
@@ -260,7 +109,26 @@ single company.
LoRa chips are just trancievers, an MCU with LoRa stack is required.
:::
-## ESP8266 details - Power usage
+## ESP8266 Specifications
+
++-------------+-----------------------------+
+| CPU | Tensilica Xtensa L106 |
++-------------+-----------------------------+
+| Frequency | 80MHz (160MHz possible |
++-------------+-----------------------------+
+| RAM | 32 kB instruction RAM |
+| | 80 kB user RAM |
+| | 16 kB system RAM |
++-------------+-----------------------------+
+| Flash | None, integrated SPI driver |
++-------------+-----------------------------+
+| Peripherals | 16 x GPIO |
+| | I²C, SPI, I²S, UART |
+| | 10 bit ADC |
+| | Wi-Fi |
++-------------+-----------------------------+
+
+## ESP8266 Power usage
+--------------------------+----------------+
| State | Current usage |
@@ -282,6 +150,61 @@ Datasheet page 18
:::
+# NodeMCU
+
+!comment(aka NodeMCU aka ESP-12)
+
+## NodeMCU hardware
+
+!ifndef(QUICK)(
+\begin{center}
+!include(images/nodemcu.pgf)
+\end{center}
+)
+
+## NodeMCU hardware
+
+!ifndef(QUICK)(
+![](images/NodeMCU-–-Board-de-desarrollo-con-módulo-ESP8266-WiFi-y-Lua-4.jpg)
+)
+
+## ESP8266 software layers
+
+!ifndef(QUICK)(
+\begin{center}
+!include(images/esp+arduino-sdks.pgf)
+\end{center}
+)
+
+## ESP8266 + Arduino
+
+* Standard Arduino IDE
+* ESP8266 Arduino core
+ * https://github.com/esp8266/Arduino
+
+## Arduino IDE
+
+!ifndef(QUICK)(
+![](images/arduino-ide.png)
+)
+
+## Generic Arduino APIs
+
+~~~c++
+// Pin: D0, D1, etc.
+// Mode: OUTPUT, INPUT, INPUT_PULLUP
+// State: HIGH, LOW, 1/0
+
+void pinMode(pin, mode);
+void digitalWrite(pin, state);
+int digitalRead(pin);
+
+unsigned long now = millis();
+unsigned long now = micros();
+~~~
+
+# Assignment: `blink-a-led`
+
# Lecture: MQTT
## MQTT
@@ -313,7 +236,7 @@ Version 3.1.1 er den som gjelder, V 3.1 er rar, de andre finnes ikke
\end{center}
)
-## MQTT Topic
+## MQTT Example
The temperature sensor:
@@ -343,41 +266,6 @@ Commands can be:
:::
-## MQTT - Implementations
-
-* Mosquitto
-* Eclipse Paho
-* RabbitMQ
-* ActiveMQ
-
-::: notes
-
-RabbitMQ has a separate connector that must be installed
-Not sure about ActiveMQ but it is at least a part of the project so it is releases at the same time.
-
-:::
-
-## MQTT Cloud Connectors
-
-* Cloud
- * Amazon IoT
- * Google Cloud IoT
- * Microsoft Azure IoT
- * CloudMQTT (at Heroku)
-
-* DIY
- * ThingMQ
- * HiveMQ
-
-::: notes
-
-In between are:
-
-* self hosted
-* Generic bridges
-
-:::
-
## MQTT - The protocol
Agents have one of two roles:
@@ -392,8 +280,8 @@ Agents have one of two roles:
* Keeps subscriptions
* Manages client
* Timeouts and disconnects
- * *(last) will*
- * Persistence of retained messages
+ * *last will*
+ * Persistence of *retained* messages
::: notes
@@ -418,76 +306,68 @@ Push vs pull, central applications can push to clients
* `foo/bar/?`
* `foo/#`
-## MQTT - The protocol - Retained message
-
-Message is kept by the server even after disconnect
-
-* `CONNECT`
-* `PUBLISH`
- * `RETAIN`
- * `$app/$device/temperature`
- * `22.3`
-* `DISCONNECT`
-
-Later on:
-
-* `SUBSCRIBE`
- * `$app/#/temperature`
-* `PUBLISH`
- * `$app/$device/temperature`
- * `22.3`
-
-::: notes
+## ESP Arduino APIs
-The last PUBLISH is an incoming message
+~~~c++
+class {
+ void restart();
+ uint32_t getFreeHeap();
+ uint32_t getChipId();
-:::
+ ...
+} ESP;
-## MQTT - The protocol - Will message
+// Usage
+ESP.restart();
+~~~
-Message sent when you disconnect
+## Connecting to a Wi-Fi
-Client #1:
+~~~c++
+#include <ESP8266WiFi.h>
-1. `CONNECT`
- * `WILL TOPIC: $app/$device/online`
- * `WILL PAYLOAD: 0`
-1. `PUBLISH`
- * `$app/$device/online`
- * `1`
-1. `DISCONNECT`
+void setup() {
+ WiFi.mode(WIFI_STA);
+ WiFi.begin("NDC2018", NULL);
-Broker
+ while (WiFi.status() != WL_CONNECTED) {
+ delay(500);
+ Serial.print(".");
+ }
-1. *To all subscribers* `PUBLISH`
- * `$app/$device/online`
- * `0`
+ Serial.println("");
+ Serial.println("WiFi connected");
+ Serial.println("IP address: ");
+ Serial.println(WiFi.localIP());
+}
+~~~
## MQTT on Arduino
PubSubClient is our MQTT client implementation.
+Preparing to publish messages:
+
~~~c++
+#include <ESP8266WiFi.h>
#include <PubSubClient.h>
WiFiClient wifiClient;
PubSubClient mqtt(wifiClient);
-void callback(char* topic,
- byte* payload,
- unsigned int length);
+String deviceId = "esp-" + String(ESP.getChipId(), HEX);
void setup() {
- // Configure WiFi
- mqtt.setServer(mqtt_server, 1883);
- mqtt.setCallback(callback);
+ // ...
+ mqtt.setServer("broker.hivemq.com", 1883);
}
~~~
## MQTT on Arduino
~~~c++
-void loop() {
+void loop()
+{
if (!mqtt.connected()) {
reconnect();
}
@@ -497,71 +377,52 @@ void loop() {
// Do work
}
+~~~
-void reconnect() {
+## MQTT on Arduino
+
+~~~c++
+void reconnect()
+{
do {
Serial.println("Connecting to MQTT");
delay(1000);
- } while (!mqtt.connect(client_id));
- Serial.println("Connected to MQTT server");
+ } while (!mqtt.connect(clientId.c_str()));
- // Subscribe to any topics you need
- mqtt.subscribe(topic_pattern);
+ Serial.println("Connected to MQTT server");
}
~~~
-::: notes
-This is blocking!
-:::
-
-## Assignment
-
-* `mqtt`
-
-## MQTT topic architecture
-
-The central application is split:
-
-* An aggregating agent:
- * `myapp/#/temperature`
- * `myapp/#/humidity`
-* Emailing agent
- * `myapp/$device-id/altert`
-
-* Publishes on:
- * `myapp/$device-id/command`
-
-## MQTT topic architecture
-
-!ifndef(QUICK)(
-\begin{center}
-!include(images/mqtt-example-architecture.pgf)
-\end{center}
-)
-
-## MQTT topic architecture
-
-!ifndef(QUICK)(
-\begin{center}
-!include(images/mqtt-example-architecture2.pgf)
-\end{center}
-)
-
-## MQTT - Patterns
-
-* Combining MQTT and HTTP
-* Using web sockets transport
+## MQTT on Arduino
-## Assignment
+~~~c++
+void sendMessage()
+{
+ String topic = "ndc/" + deviceId + "/led";
+ mqtt.publish(topic.c_str(), "1");
+}
+~~~
-* `mqtt2`
+## MQTT on Arduino
-## Assignment
+Preparing for subscriptions:
-* `mqtt3`
+~~~c++
+void setup() {
+ ...
+ mqtt.setCallback(callback);
+}
-::: notes
+void callback(char* topic,
+ byte* payload,
+ unsigned int length) {
+}
-discussion: how to connect these two devices?
+void reconnect() {
+ ...
+ // Subscribe to any topics you need
+ mqtt.subscribe(topic_pattern);
+}
+~~~
-:::
+# Assignment: `mqtt-with-button`
diff --git a/slides/toc.md b/slides/toc.md
index 227f00a..d137e28 100644
--- a/slides/toc.md
+++ b/slides/toc.md
@@ -1,40 +1,33 @@
+* What is IoT
+ * What is IoT
+ * IoT is just a concept
+ * What is an IoT Device?
+ * What is an IoT Device?
+ * IoT Devices - Example chips
+ * ESP8266 Specifications
+ * ESP8266 Power usage
* NodeMCU
* NodeMCU hardware
* NodeMCU hardware
* ESP8266 software layers
* ESP8266 + Arduino
* Arduino IDE
- * Arduino code structure
- * Arduino file structure
* Generic Arduino APIs
- * ESP Arduino APIs
- * ESP
-#include <ESP8266WiFi.h>
- * ESP Arduino APIs
-* What is IoT
- * What is IoT
- * IoT is just a concept
- * What is an IoT Device?
- * What is an IoT Device?
- * IoT Devices - Example chips
- * ESP8266 details - Power usage
+* Assignment: `blink-a-led`
* Lecture: MQTT
* MQTT
* Device and application architecture with MQTT
- * MQTT Topic
- * MQTT - Implementations
- * MQTT Cloud Connectors
+ * MQTT Example
* MQTT - The protocol
* MQTT - The protocol - MQTT Topic
- * MQTT - The protocol - Retained message
- * MQTT - The protocol - Will message
+ * ESP Arduino APIs
+ * Connecting to a Wi-Fi
+#include <ESP8266WiFi.h>
* MQTT on Arduino
+#include <ESP8266WiFi.h>
#include <PubSubClient.h>
* MQTT on Arduino
- * Assignment
- * MQTT topic architecture
- * MQTT topic architecture
- * MQTT topic architecture
- * MQTT - Patterns
- * Assignment
- * Assignment
+ * MQTT on Arduino
+ * MQTT on Arduino
+ * MQTT on Arduino
+* Assignment: `mqtt-with-button`