cat /sys/firmware/devicetree/base/model
There appear to be three main ways:
In short, using Photoshop is probably the best way to download images from an iPhone, although they must be on the device, not stored on iCloud with smaller versions downloaded kept on the phone...
As the USB to UART doesn't appear to work with Windows 11, an alternative is to connect the RPi direct to the laptop. A tutorial on how to do this can be found here.
There are instructions on how to install Google Play on oa Kndle at howtogeek.com.
However, it is also possible to simply download the APK file from apkmirror.com.
It is easiest to copy the .apk file to a micro SD card to transfer it to the kindle. The app is installed through simply selecting it in the Files app on the kindle.
To manage remote repositories in Git:
# to view current remotes
git remote -v
# to update the URL
git remote set-url
/etc/ssh/sshd_config to set:
ClientAliveInterval 60
ClientAliveCountMax 10
/etc/ssh/ssh_config: ServerAliveInterval 60
ServerAliveCountMax 10
Note that Pi4j v1.4 relies on Java 11, whcih will cause issues with older models of Raspberry Pis.
Therefore, mosly best to stick to v1.3, and disable the repo in /etc/apt/sources.list.d/pi4j.list
Pi4j v2.0 is next..
VS Code Remote Development is fantastic, but it doesn't support the Raspberry Pi Zero as the armv6l isn't supported.
However, this it is possible to mount /home/pi as a Samba share and amend files locally, which will perform similarly (for Python development anyway).
This is described here. Install Samba with:
sudo apt install -y sambaThen add the following to /etc/samba/smb.conf as follows:
[PiShare]
comment=Pi Share
path=/home/pi
browseable=yes
writeable=yes
only guest=no
create mask=0740
directory mask=0750
public=noNote that the Samba configuration file can be checked with the testparm command.
Finally, set a password with sudo smbpasswd -a pi. This will create the Samba user pi.
This can be accessed from another computer on the network as \\hostname\share
APT (Advanced Packaging Tool) is a set of tools that was developed for Debian Linux platform as an easy command line interface for the dpkg utility
apt update
apt upgrade
apt install python3
apt install ./pi4j-1.3.deb # install local package
apt show python3
apt remove python3
apt list # lists all available packages
apt list --installed # lists installed packages
apt list python3 # also shows if package is installed
apt search python3
# list all files contained in the package
dpkg -L python3
# find which package contains a file
dpkg -S /usr/bin/python3
wpa_supplicant.conf file in the root of the SD card
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=GB
network={
ssid="ssid"
psk="psk"
}
raspi-config to set hostname, interfaces etc.sudo apt install default-jdk
# or for older RPi mmodels
sudo apt install openjdk-8-jdk liblog4j2-java wiringpi libmysql-java
Edit: turns out these can now be set up with the Raspberry Pi Imager v1.6, which is a lot easier...
Note that this doesn't appear to work with Windows 11...
Rows from two tables can be combined using joins.
Inner joins return only the rows that meet the specified condition in both tables.
# keyword INNER is optional
SELECT * FROM toys
INNER JOIN bricks
ON toy_id = brick_id;
# Oracle syntax
SELECT * FROM toys, bricks WHERE toy_id = brick_id;
Outer joins return all the rows from one table, along with the matching rows from the other. Rows without a matching entry in the outer table return null for the outer table's columns.
An outer join can either be left or right, which determines which side of the join the table returns all rows for.
# keyword OUTER is optional
SELECT * FROM toys
LEFT OUTER JOIN bricks
ON toy_id = brick_id;
SELECT * from toys
RIGHT JOIN bricks
ON toy_id = brick_id;
A full join includes unmatched rows from both tables. This is not supported directly by MariaDB.
SELECT * FROM toys
FULL JOIN bricks
ON toy_id = brick_id;
SELECT * FROM toys
CROSS JOIN bricks;
See also here
This should reconnect a Raspberry Pi if it drops from the network due to router issues...
*/5 * * * * /bin/ping -q -c10 192.168.1.254 > /dev/null 2>&1 || (sudo /sbin/ifconfig wlan0 down ;sleep 5 ;sudo /sbin/ifconfig wlan0 up ;/usr/bin/logger wifi on wlan0 restarted via crontab)
First, connect to the pi using the USB to UART cable, following the instructions at Adafruit, and enabling the connection in /boot/config.txt
Then set up wifi following the instructions at raspberrypi.org.
Then change the default password using:
sudo passwd piThen enable SSH, and update the hostname using:
sudo raspi-config
# Select Interfacing Options and enable SSH
# Select Network Options and change hostname Finally, update the software with:
sudo apt update
sudo apt upgradeCommand Prompt isn't great, so Windows Terminal is welcome.
However, as with VSCode, it feels a little clunky to use and setup, primarily due to the use of a JSON file to hold the settings.This file is (unhelpfully) found at
%USERPROFILE%\AppData\Local\Packages\Microsoft.WindowsTerminal_8wekyb3d8bbwe\LocalStateSettings are documented at Terminal Documentation, but the key settings are documented here:
{
...
"initialCols": 100,
"initialRows": 64,
"initialPosition": "80,10",
"profiles":
{
"defaults":
{
"fontSize": 9,
// or consolas...
"fontFace": "Cascadia Code",
"useAcrylic" : true,
"acrylicOpacity" : 0.85,
"closeOnExit": true
},
"list":
[
{
"guid": "{61c54bbd-c2c6-5271-96e7-009a87ff44bf}",
"name": "Windows PowerShell",
"commandline": "powershell.exe",
"hidden": false,
"colorScheme": "One Half Dark"
},
{
"guid": "{2c4de342-38b7-51cf-b940-2309a097f518}",
"name": "Ubuntu",
"source": "Windows.Terminal.Wsl",
"hidden": false,
"colorScheme": "Solarized Dark",
"startingDirectory":"//wsl$/Ubuntu/home/paul/"
},
{
"guid": "{0caa0dad-35be-5f56-a8ff-afceeeaa6101}",
"name": "Command Prompt",
"commandline": "cmd.exe",
"hidden": false,
"fontFace": "consolas",
"fontSize": "16"
}
]
}
}
Useful keys are:
There is a great App for Chrome called Stop Motion Animation that is a very simple and straightforward way of creating stop motion videos.
It is straightforward and easy to use, and the kids love it.
However, it does produce files in webm format. These can be played in VLC Media Player but they can't be run in Windows Media Player.
However, they can be converted to mp4 using ffmpeg, which can be installed on either a Raspberry Pi or WSL.
# install if necessary...
sudo apt-get install ffmpeg
# then run
ffmpeg -fflags +genpts -i filename.webm -r 96 filename.mp4
Note sure about the correct frame rate, but this appears to work in this instance...
This article is probably also worth a read (though I haven't yet)...
Some versions of the Raspberry Pi/ Raspbian have NTP disabled
# to check status
timedatectl status
# to enable NTP...
sudo timedatectl set-ntp True
Finally found at how to do this using prism.js from the excellent blog post here.
This is done by adding a link to the CSS in <head>, and a link to the JS before closing the <body> tag. The theme is specified with the css name, e.g. prism.min.css or prism-tomrrow.min.css. For Blogger, this has to be done by updating the Blog Theme.
<head>
...
<link
href='https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/themes/prism-tomorrow.min.css'
rel='stylesheet'/>
</head>
<body>
...
<script
src='https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/prism.min.js'/>
<script
src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/plugins/autoloader/prism-autoloader.min.js"/>
</body>
There is a full list of the CDN files here, and a full list of supported languages here.
Code is enclosed within the <pre> tag to preserve formatting; and within the <code> tags, also specifying the language for highlighting:
<pre><code class="language-java">class App { public static void main(String[] args) { System.out.println("Hello World!"); } }</code></pre>
Formatting can also be done inline.
Note that to display HTML or PHP some of the symbols will need to be escaped so the browser doesn't try to parse the code. An online converter like Free Online HTML Escape Tool can do this.
pip install esptool
# erase the flash
esptool.py --chip esp8266 erase_flash
# For the HUZZAH ESP8266 breakout buttons for GPIO0 and RESET are built in to the board
# Hold GPIO0 down, then press and release RESET (while still holding GPIO0),
# and finally release GPIO0
# install the firmware
esptool.py --chip esp8266 --port COM3 write_flash --flash_mode dio \
--flash_size detect 0x0 esp8266-20190529-v1.11.bin