21 votes
Accepted

Selecting a microcontroller for a battery operated data collection project

A general process of microcontroller selection. Sum up your requirements towards the microcontroller. For example in this case: 1 hardware timer, to measure time between trigger and echo pulses. 2 ...
17 votes

Is there a way to turn on large numbers of IoT devices remotely?

In as much as there is a 'standard' solution I suspect it's going to look like a Wi-Fi enabled microcontroller attached to a relay or MOSFET. Something somewhere has to be on 24/7 if you want round-...
  • 272
16 votes

Battery backup for small IoT devices?

You can hook up a USB battery pack to both the Pi and the charger (as long as it is designed to charge while being used) and if the power goes out the USB battery pack will take over powering the Pi ...
  • 161
16 votes
Accepted

Cheap IoT microcontroller with PoE

Orange Pi Zero is cheap (7$ + shipping), can be hacked to run on passive PoE, supports TCP/UDP over on-board ethernet and wireless and has a few I/Os. It's not exactly a microcontroller in my book, ...
16 votes

As a Computer Science student, how can I develop skills for an IoT job outside of formal education?

I have been a university tutor in a department that now teaches IoT and your observations are right when it comes to getting your hands dirty with some toys rather than just a degree. A lot of ...
  • 1,458
15 votes

How can I properly test my device's PCB antenna?

You can use a spectrum analyzer to make sure that: The antenna is emitting at the correct frequency (range). The output power is the expected (theoretically calculated) output power (or it is close ...
  • 251
14 votes

How does an experienced developer get started with IoT

This is a very broad question, but I will try to give a few general pointers, hopefully useful to others, as well as you (so, please accept my apologies if I post things which you already know). If ...
14 votes
Accepted

How does an Azure IoT Hub interact with Embedded/IoT devices?

The model that IoT Hub connected devices use is that they will never accept incoming connections. IoT Hub devices never act as a 'server', and this is a crucial part of the security model in Azure IoT....
  • 1,483
13 votes
Accepted

Would RPI 3 serve as IoT server with MQTT?

A Raspberry Pi 3 is a pretty serious bit of kit when you think about it Quad core Arm Cortex 1gb of RAM a onboard GPU That is a huge amount of memory, easily more than enough to run a MQTT broker ...
  • 12k
12 votes

Are there any devices with open-source protocols over Wi-Fi?

The IKEA Trådfri lighting system is all CoAP based, you can find my write up on the protocol here Belkin WeMo devices are all uPnP and SOAP controlled as well so another open/self describing protocol
  • 12k
11 votes

Which microcontroller and programming language should I use for an Internet-enabled weather display?

The Onion Omega 2 claims to be the smallest Linux computer in the world. That claim may not quite be true (see the vocore2 below, for example) but in my experience it's got to be in the smallest 3. ...
  • 211
11 votes

How can I properly test my device's PCB antenna?

There are two main approaches to characterising an antenna and its effectiveness in-system, free space and in-situ. The first will give you a best-case baseline, is less susceptible to measurement ...
11 votes

Cheap IoT microcontroller with PoE

You do not need PoE for your setup. Just use two wires from Ethernet cable to power your controllers. Ethernet cables have four unused wires: 4 (blue), 5 (white with blue), 7 (white with brown) and 8 ...
11 votes

What are affordable solutions to air quality monitoring system?

I think it's non-existent today. I work at a Dutch municipality and, though things might have changed now, in December 2017 our environmental department concluded that even semi-professional gas or ...
  • 533
10 votes
Accepted

Reusing / recycling a Petzi Treat Camera?

Electronics are generally recyclable, that is not something specific to IoT devices. More specifically, your IoT device will typically provide a general purpose MCU. Recycling an MCU is generally ...
9 votes

How does an experienced developer get started with IoT

As an experienced developer you have the ability to understand logic, read and write code, figure things out, and some other important skills. What you probably don't have is an understanding of basic ...
  • 1,483
9 votes

Battery backup for small IoT devices?

If possible choose a device that has a built in battery. A few such examples that use the common 2-pin JST connector. The first two are based off of the esp8266 WioLink WioNode C.H.I.P ($9 computer)...
  • 551
9 votes

Cheap IoT microcontroller with PoE

Arduino do a board with built in PoE, but at double the price of a Pi last time I looked, I would not consider it cheap. And sounds physically bigger than you are looking for. The is also the Arduino ...
  • 12k
9 votes

Power reduction for Raspberry Pi GPS/GSM tracker

I'll assume that the processing requirements on the device are near enough zero. It sounds like you're using some acceleration input to determine how often to wake up the GSM device. Ideally, you ...
9 votes
Accepted

Arduino Uno Vs Raspberry Pi

This is widely discussed over the net, but, those are different things. Which one is better, it will depend on what you're building. My way of choice is: If I want device that reads a sensor and ...
  • 804
8 votes

How can I properly test my device's PCB antenna?

In order to properly test the antenna at minimum the following items are required A source antenna with the known pattern and transmitter such as a RF signal generator create known signals The test ...
8 votes

Making a smart light switch

By far the easiest route is to buy an exisiting product here which is sufficiently open that you can use a standard RF module to control them. This is equivalent to having an MCU and switch ...
8 votes
Accepted

Looking for a relay that can be controlled from .net web application (via TCP/IP)

There are a lot of devices out there that allow you to control digital I/O over a network. The difference between this and relay control is very little as you can very easily add a Solid State Relay ...
8 votes

Drawing parallels between building an IoT system and building a PC?

The generics first Some of the candidates only talk about what they learned from building PCs Coming from PCs is not a problem, but, candidate should understand that an IoT device/product/...
  • 2,560
7 votes

Making a smart light switch

If you want a totally independent switch in case of the microcontroller fails, then you can hook-up an XOR gate for two inputs. The relay will be off when both inputs are the same, and on if the ...
7 votes
Accepted

How can I detect Alexa's current state or change its current state with an external device?

This open source Raspberry PI Alexa client has support for free wake words made as easily from PI's terminal as: sudo systemctl stop AlexaPi.service sudo nano /etc/opt/AlexaPi/config.yaml change ...
  • 4,301
7 votes
Accepted

UK-compatible (240VAC) receiver/controller for ceiling fan with dimmable lights

The good news for you is that the choice of fan-speed and lighting control is often independent of the actual ceiling fan itself. Most lighted ceiling fans operate using two independent circuits; the ...
  • 2,422
7 votes

Which microcontroller and programming language should I use for an Internet-enabled weather display?

Creating a startup is not about what you can do with the technology and not even about the product. For a successful startup that can captivate VC's you should first think about the market that you ...
7 votes

Which microcontroller and programming language should I use for an Internet-enabled weather display?

I suggest a step by step approach to find out what language and controller you should use. The microcontroller you need will depend on the tasks you want it to do. Theoretically the task will set up ...
7 votes

As a Computer Science student, how can I develop skills for an IoT job outside of formal education?

IoT runs the gamut of computing, and covers a huge range of technologies, implementations, and tactics. The nutshell is that it just means things are connected to a comms channel, e.g., the internet. ...

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