hcheung
  • Member for 5 years, 1 month
  • Last seen more than a week ago
MySQL initial installation
Accepted answer
6 votes

mariadb by defaults uses UNIX_SOCKET plugin to authenticate user root. https://mariadb.com/kb/en/mariadb/unix_socket-authentication-plugin/. It works by retrieving uid of the process that has ...

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Using single 5V relay (jqc-3ff-s-z) - safety advice required
5 votes

The Relay module in your picture is what so called Relay shield specific designed for directly interfacing with micro controller such as Raspberry Pi or Arduino, the board already consists of the ...

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No module named 'RPi.GPIO'
4 votes

You didn't mentioned what OS distro you are using. But if you are using Raspbian Stretch, RPi.GPIO is included in default installation of Python 2.7, but it does not seems to be included in Python 3.5 ...

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Is it possible to host a website on the Pi3 with 1GB ram?
3 votes

Yes, you can definitely do that. Raspberry Pi 3 is surprisingly capable. I recently put up a self-hosted website on a Raspberry Pi 3 running Nginx, PHP5 and MariaDB with HTTPS and WordPress. Security ...

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How can I display sensor data on webserver by php?
2 votes

Since you are aware of LAMP, the short answer would be go ahead to install LAMP and learn how to use it. But there is a simpler solution for beginners and for python programmers. Since you are using ...

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Security implications of running my website on my raspberry pi
2 votes

Renting a Virtual Private Server (VPS) is not necessary more secure than running on RPi, and you still going through almost the same processes in setting it up, unless you go for full hosting service. ...

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How can I install numpy and pandapower?
2 votes

By default, Jessie Lite for Raspberry Pi have python 2.7 installed but does not have pip/setuptools/wheel installed. To install pip, run: sudo apt-get install python-pip This will install setup ...

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w1-gpio and DS18B12 always return t=85000
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2 votes

As per @Ghanima's suggestion, repost my updated as a separate answer. I've solved the problem by myself by changing the /boot/config.txt settings from dtoverlay=w1-gpio to dtoverlay=w1-gpio, ...

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Python 3 default python
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2 votes

If you run linux command ls -l python* within the directory, you will see that python is just a symlink to python2.7, if you know linux commands well enough, you can easily make a change to link ...

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How to connect a Raspberry Pi to an RCA based display with sound?
2 votes

To be sure, you can get a cable from Adafruit to ensure that the cable is for RCA display product (versus RCA output product).

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Need help setting up SSH Tunnel with Motion Pi surveillance system
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1 votes

If you are using Stunnel, you probably don't need an SSH tunnel unless you have a specific reason. Stunnel is designed to work as a TLS encryption wrapper between client and server so that whatever ...

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Switch audio output not working
1 votes

If you are on Raspbian, Run sudo raspi-config Navigate to 7 Advanced Options => A4 Audio => Force 3.5mm ('headphone') jack, save and reboot.

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TCP server on raspberry pi not connecting to android tcp client
1 votes

1) You can set host to host = '0.0.0.0' or host=''. 2) You don't really need an Android phone to test the socket connection, all you need is to run another session of terminal on your computer or ...

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Raspberry Pi SSH suddenly doesn't work
1 votes

When you re-install OS on the SD card, the public key for SSH on the SD card changed even though the host name (i.e. pi@10.255.7.130) remain the same, but your computer (SSH client) still have the old ...

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Monitor problem when turning on relays
1 votes

To your question about when there are two grounds, it is no longer a Raspberry Pi related question. However I hope a quick explanation will help those Raspberry Pi users tinkering with electronics ...

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Using Python's Rpi.GPIO library to manually toggle SPI chip select. Is this OK?
1 votes

If you read the SpiDev github, SpiDev has an option that you can set to ignore CS. spi.no_cs = True # Set the "SPI_NO_CS" flag to disable use of the chip select You may still want to set the CS ...

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Potentiometer on 16x2 LCD, does it need to be connected to VCC?
Accepted answer
1 votes

Both way you described (either using a potentiometer as a voltage divider, or connecting a resistor between the contrast control pin (Vo) and ground) are valid configuration. The contrast of the LCD ...

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BCM.GPIO and BOARD.GPIO
1 votes

The library Adafruit_Python_SSD1306 is based on another library Adafruit_GPIO, if you read the Adafruit_GPIO github source code on get_platform_gpio(**keywords) function, you will noticed that it is ...

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Static Ip on Device or via Router
1 votes

It will make more sense to setup "IP and Mac binding" on your router in your case for whatever reason you'd want to run multiple OS. The procedure varies from router to router, but all you need is the ...

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How to choose appropriate transistor and resistor values for the 4 digit display?
1 votes

First of all, you had some basic concept wrong. When an LED is on, the voltage between the anode and the cathode of the LED is minimum, only about 0.5-0.7v. This is why the tutorial said that the ...

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Connecting to Pi3 Model B automatically to wifi using WEP
Accepted answer
1 votes

First, WEP key (i.e. password) only allowed hexadecimal digits (i.e. 0 - 9, A - F) as password, therefore 'hello' is not a valid password, and maximum length for the password is 26 hexadecimal digits (...

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Can't install node
Accepted answer
1 votes

One of the problem about those online tutorials is that they are obsoleted and never bother to update it, and many tutorials were prior nodejs has the official binary package for ARM CPU which ...

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Using 2 different networks on Raspberry Pi
1 votes

1) First since the release of Jessie, many tutorials or past posts of changing the /etc/network/interfaces became obsoleted. It was common in previous OS release to make changes directly to the /etc/...

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How can I boot Pi zero with SSH over USB
Accepted answer
1 votes

If your SD card is newly created, by default SSH is not enable on the first boot. SSH can be enabled by placing a file named 'ssh', without any extension, onto the boot partition of the SD card. This ...

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Can't port forward when usb0 is connected
1 votes

What is your network mask setting you see when you run ifconfig? If your network mask is set as Mask:255.255.255.0, your phone and wifi are basically on two different networks, you can either change ...

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Cannot use 'apt-get' at all
1 votes

If I look at http://mirrordirector.raspbian.org/raspbian/pool/main/j/jq/, the file (http://mirrordirector.raspbian.org/raspbian/pool/main/j/jq/jq_1.4-2.1_armhf.deb) that the package try to update ...

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Linux (Raspbian ) on raspberry pi 3 “hangs” after a random period of time, how to debug?
Accepted answer
1 votes

What do you get when you ping the IP or run curl -I xxx.xxx.xxx.xxx (Your IP address or web url)? Are you using an internal IP or public IP? One problem that I see for self-hosted server with SSH port ...

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Raspberry pi: Arduino to Python
Accepted answer
0 votes

Data communication are often serialised and transmit in byte instead of string. Bytes in python are indicated by the prefix b in front of the data as you shown b'FF6897\r\n' but you are trying to ...

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problem with name domain resolution (I believe)
0 votes

This happened quite often lately with Raspbian Stretch, somehow running apt-get update screw up the gateway setting. This can be observed by run the following command: route -n Kernel IP routing ...

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Recording time series data from Bluetooth by Pybluez
Accepted answer
0 votes

You didn't provide the full program so it is hard to know what you are missing, but I think you probably setting up the client mix up the client/server relationship. import bluetooth # setup server ...

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