Last call to make your voice heard! Our 2022 Developer Survey closes in less than a week. Take survey.

Hot answers tagged

11 votes

mosquitto_sub: command not found

The solution is to install mosquitto-clients as well. pi@raspberrypi:/ $ apt-get install mosquitto-clients Reading package lists... Done Building dependency tree Reading state information... Done ...
user avatar
  • 291
11 votes
Accepted

Is there a way to control my lights from my Linux desktop?

Belkin WeMo devices use uPnP and SOAP messages for control so can be easily controlled from any number of languages and options. Some details on the work I've done working out the protocol can be ...
user avatar
  • 11.9k
10 votes
Accepted

What will happen if I use Class 4 SD card, instead of recommended Class 10 for Intel Galileo?

Any read/write operations will be slower. However, if you don't want to stream Full HD videos or other heavy content that requires that kind of data transmission rates you'll be fine. Most of the time ...
user avatar
  • 8,045
10 votes
Accepted

mosquitto_sub "connection refused" on Arch Linux

Turns out there is no broker running on the Arch system whereas installing mosquitto on Raspbian automatically starts it. Simply enable and start the broker. Start the systemd service. systemctl ...
user avatar
  • 2,419
7 votes

SSH into an Orange Pi connected to the internet via 2G GSM module

Most cellular providers use Private IP (RFC-1918) ranges (e.g. 10.0.0.0/8) and NAT for their networks which means it is not possible to directly access a device connected via these networks remotely ...
user avatar
  • 11.9k
7 votes
Accepted

Why does Docker reduce power usage on an Internet of Things device in this benchmark?

After some further investigation, I think the issue in the question is that although the power (rate of energy transfer) was reduced, the overall energy consumption was increased by using Docker, so ...
user avatar
6 votes

Controlling IoT device through a captive portal/web app over Wi-Fi & 4G/LTE simultaneously

Question 2.) Are there any other ideas that anyone can think of to solve this - even crazy ideas like XSS vectors to PUSH content into the captive portal from external servers? If I may suggest, you ...
user avatar
  • 2,560
6 votes

What will happen if I use Class 4 SD card, instead of recommended Class 10 for Intel Galileo?

There are 4 standard SDA ratings that I'm aware of: 2, 4, 6, and 10. Basically, the number corresponds to the minimum write speed in MB/s that the card is capable. So for instance, a Class 4 would ...
user avatar
  • 4,613
5 votes
Accepted

SBC similar to Banana/Raspberry Pi with USB comms

The Raspberry Pi Zero (and Model A) have just one USB port and as such can be used in device mode (it's the USB hub used to give the extra ports and the ethernet that stops the USB controller working ...
user avatar
  • 11.9k
5 votes
Accepted

Is it okay to use the 4 pin USB TTL cable instead of the recommended 6 pin USB TTL cable for Intel Galileo?

CTS and RTS are for flow signaling (Clear To Send) and (Request To Send). If you want to use 4 pins and you find out nothing is flowing through, you may want to pull CTS down to GND. In one post OP ...
user avatar
  • 4,301
5 votes

Edison Ubilinux Flash Error "Cannot allocate memory of size 1610612736"

Right click on Computer and open Properties. Select Advanced System Properties Click Advanced tab Under Performance, click Settings Under Performance Options, click Advanced tab Here under Virtual ...
user avatar
4 votes

Is there a way to control my lights from my Linux desktop?

There are sooooo many ways to do what you ask for. There are proprietary solutions with API's and there are Open solutions with total openness. Your question is broad and hard to give a straight ...
user avatar
  • 762
4 votes
Accepted

Which tools/frameworks do you use to configure an array of SBCs

There are several ways that you can create a modified distro, and the best approach will depend on your environment and how you anticipate that evolving over time. Yocto is good if you need to apply ...
user avatar
4 votes

Which tools/frameworks do you use to configure an array of SBCs

One of the choices for creating Embedded Linux distributions is Yocto. Yocto is open source collaboration project that provides templates, tools and methods to help you create custom Linux-based ...
user avatar
  • 2,560
4 votes

Using Raspberry Pi as USB bridge

A Full sized Raspberry Pi ( not a Pi Zero or Pi A) with more than 1 USB port can not act as a USB device. This is because to get 4 USB ports the USB controller is hard wired to a USB hub on the board. ...
user avatar
  • 11.9k
4 votes
Accepted

Make Embedded Board NTP Server for Arduino boards in the subnet

Precise Description for the Query Initial NTP time sync In the Yocto build system under conf/local.conf add ntp recipe as follows: IMAGE_INSTALL_append = " ntp" on Target board initially stop the ...
user avatar
  • 1,458
4 votes
Accepted

How to use SSH server on a remote device and overcome routing issues

Don't try and solve this with trying to connect to the device the wrong way through NAT. Approach this the other way round, have the device connect out to a known point (e.g. a cloud host) which can ...
user avatar
  • 11.9k
3 votes

Entropy depletion in /dev/random on Beaglebone

The local work-around for me was run rng-tools directly from rc.local: $ cat /etc/rc.local #!/bin/sh -e # # rc.local # # This script is executed at the end of each multiuser runlevel. # Make sure ...
user avatar
  • 279
3 votes
Accepted

Is the LinkIt 7688 Unofficially Unsupported?

Mediatek provide it's own binary wifi driver in its feeds based on old 15.05 OpenWrt version. It seems not updated since years (https://github.com/MediaTek-Labs/linkit-smart-7688-feed). Hard to know ...
user avatar
  • 151
3 votes

Remote com (serial) connection through cellular IoT

If I get your question correctly, you want to gather data from the IoT devices using a serial protocol over rs232/485. and then send this data onto some remote server using the cellular data. If that ...
user avatar
  • 429
3 votes
Accepted

How to cross compile Paho-MQTT-C library for ARM?

You are facing these build errors as you are missing the sysroot corresponding to the arm-gcc that you are using as your CC. You may try changing the Makefile as follows: diff --git a/Makefile b/...
user avatar
  • 2,560
3 votes

SBC similar to Banana/Raspberry Pi with USB comms

In order to use USB gadget mode, you either need two USB controllers native on the device (so one can act as master, and one as slave), or all of the other peripherals (Bluetooth, Wifi, Ethernet, ...
user avatar
3 votes

How to secure root on IoT device while remaining open to tinkerers

Assuming you need to handle firmware updates (otherwise, you're insecure by default) then you will also need to sign the updates (and manage updates in a secure way). Otherwise, an attacker can simply ...
user avatar
3 votes
Accepted

How to secure root on IoT device while remaining open to tinkerers

Great question! Several things you should keep in mind. 1. Default passwords This is really basic, and you've probably already thought of it, but let me reiterate: default or easy passwords are ...
user avatar
  • 4,613
3 votes

802.11 action frames send and receive in software

I'll bet ESP-Now frames can be sniffed by tshark using something like tshark -n -l -i wlp0s29u1u2 -I -y IEEE802_11_RADIO (add a -t type such as ek or json), then add a filter like -Y 'wlan.fc....
user avatar
3 votes

Is there a way to control my lights from my Linux desktop?

If you're looking to keep clutter off of your wifi network, you could use Z-Wave or Zigbee lights (bulbs, sockets, or switches). Each of those network protocols can be run using a USB controller that ...
user avatar
  • 151
2 votes

How to setup mosquitto public broker in linux server?

If I am not wrong in understanding you question, You are trying to connect to the broker via a device which is not on the same network as the broker is. If that's the case then the thing is that MQTT ...
user avatar
2 votes

How can I review a smartphone sensors readings on a Dell gateway?

From sensors you can register a listener to sensor events [1] and on every value you send it to a ByteArrayWriter/Listener pair over socket connection [2]. Socket needs only WLAN from the gateway, ...
user avatar
  • 4,301
2 votes

802.11 action frames send and receive in software

This depends on the WiFi adapter you are using; some grant this level of access, others do not, or at least not in any documented or discovered way. Given that the ESP-series modules are comparable ...
user avatar
2 votes

Anyone know of a Wi-Fi light switch that works with Linux?

paraphrased from my answer here: You could use the Belkin Wemo Light Switch, if you can find one (apparently Belkin aren't making new ones any more). The initial configuration has to be done using ...
user avatar
  • 191

Only top scored, non community-wiki answers of a minimum length are eligible