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Table of Contents
Hands-On MQTT Usage
Background
- Although the heartbeat system used in MESHdesk / APdesk allows for remote command execution there might be situations where you need the immediate command execution.
- Security is a big thing where I stay and with this hands on lab we will see how to make use of the MQTT implementation to switch outdoor lights remotely on and off.
- For this lab we have:
- MESHdesk managing a mesh network that has the following hardware
- 3x Xiaomi 4C Units
- 2x Dragino MS14
- 1x 4 Channel Arduino Relay Module connected to one of the Dragino units.
- 3x outdoor lights connected to the 4 Channel Arduino Relay Module.
- One will be installed at the garage.
- One will be installed at the driveway.
- One will be installed at the backyard.
- !!!Insert Photo of setup here!!!
GPIO Pins of Dragino MS14
- The Dragino exposes a couple of GPIO pins on a header.
- The GPIO pins will be connected to the Arduino Relay Module.
- We will use the following mapping
| Dragino | Arduino | Comment |
|---|---|---|
| GPIO19 | In1 | Driving the relay to the garage light |
| GPIO21 | In2 | Driving the relay to the driveway light |
| GPIO18 | In3 | Driving the relay to the backyard light |
| GPIO24 | In4 | Extra for future expansion |
| 3.3v | Vcc | Use the 3.3V since the 5V is to high for the GPIO pin output to trigger a low / high |
| GND | Gnd |