raspberrypi

3239 readers
1 users here now

Community about the single-board computers, micro-controllers and related projects.

https://www.raspberrypi.com/

Other RaspberryPi communities on Lemmy

founded 4 years ago
MODERATORS
51
 
 

Pi4 1gb, posters on left with feh, info board on right which is a html file running on chromium

52
 
 

I'm sorry if this isn't the place to ask this, I also asked over at !python@programming.dev.

So what I want to do is this: Two RasPis are at different locations. They're on different networks but have internet access. Pressing a button on one of the Pis turns on an LED over at the other Pi via GPIO. How can I make the communication work? My first thought was Telegram bots as I'm familiar with those for notifications but you can't have Telegram bots communicate with each other, sadly. Is there a good (and secure) solution to this? Preferably using Python code and without continuous costs like server hosting, etc?

Thanks!

53
1
submitted 8 months ago* (last edited 7 months ago) by retrolasered@lemmy.zip to c/raspberrypi@lemmy.ml
 
 

Instructables sucks and my github's a mess, so I'm just going to post this here, so Lemmy exclusive I guess..

Before starting you will need an rpi 4b, after monitoring over ssh I'm pretty sure a 2gb model will be enough, the RAM usage didn't really get much past 1.7gb, I used an old 4gb that used to be my projects centre. Cooling is advised, you can overclock and get the performance boost that way too which helps a lot with 1080p, although still don't expect to get near that with youtube, go with piped instead. Ethernet and an overclock will get the best performance, although 720p on most sites seems to run okay over wifi. You will want to run from USB storage too, I'm using the M.2 SSD base with the argon ONE case, but I tested on a USB 3.0 thumbdrive and results were pretty similar.

Start by flashing the latest 64-bit raspi lite OS to a usb device. You may need to update the EEPROM if you haven't already in order to boot from USB. Take advantage of the rpi imager settings here to enable SSH and change the hostname so you can tell it apart from the 6 other pi's you have running around your house, if using a different imager then don't forget to include the SSH file you may need it on the next step.

After initial boot, the screen may black out, using the same image I had this happen with the USB SSD, but not the USB thumb drive. If it blacks out then ssh in and vi or nano into /boot/firmware/config.txt and comment out and add the following lines:

#dtoverlay=vc4-kms-v3d
dtoverlay=vc4-fkms-v3d

Now that the screen is working you can log into the session, and make the usual prayer sudo apt update && sudo apt upgrade -y followed by a sudo reboot for luck. And next install KDE Plasma; I originally went for kde-plasma-desktop as its the lighter install, but it kept hanging at boot, you might have more luck, but expect to start again if it fails.

sudo apt install kde-standard

After that another reboot for luck. Then we need to activate the sddm login manager service, and tell raspi OS that we want it to boot into GUI on the next boot:

sudo systemctl enable sddm
sudo systemctl set-default graphical.target

And reboot again. It should now boot into plasma, and the first thing you should do is disable all the desktop effects; older KDE plasma guides suggest to disable compositor, but the session defaults to wayland unless you tell it not to, and wayland can't run without the compositor - I've noticed no major differences between X11 and wayland myself in this use case (don't believe the hype). [edit: have found that disabling compositor in X causes screen tearing on video, so just disable desktop effects but leave compositor on]

Now the effects are disabled, and if you have your cooling set up, now is a good time to overclock, so back into /boot/firmware/config.txt. I just went with the following:

# Overclock
over_voltage=6
arm_freq=2000
gpu_freq=700

Next we can install the other bits we need:

sudo apt install chromium-browser rpi-chromium-mods plasma-bigscreen

If you want to watch DRM services like netflix you will need another package thats not included in lite:

sudo apt install libwidevinecdm0

KDE connect and an android phone make the perfect remote control, connect should already be included in the KDE install. But firewall suggested, with connect and ssh rules:

sudo apt install ufw
sudo ufw allow 1714:1764/udp
sudo ufw allow 1714:1764/tcp
sudo ufw allow 22/tcp
sudo ufw enable

Next open chromium, add the extensions you want, and "install" your "web apps".

Now open up KDE settings again, select Startup and Shutdown > Login Screen (SDDM), and then click the behaviour button at the bottom and set plasma to log in automatically and change the session to bigscreen, password to confirm, and it should prompt you to set a password for the keychain, I set a blank password because I want other people to be able to use the tv. Also disable power saving, or at least getting sent back to the login screen after sleep.

Done! Reboot and enjoy!

Some optional polish:

plasma bigscreen is designed to work one window at a time, so if you minus a window without a keyboard you've essentially lost it, so in settings you can remove the titlebar buttons for max/min and hide and just leave the one to close the window with.

Xscreensaver has a pretty cool analog tv effect screensaver that will cycle through images in a folder and display them with various tv static effects:

sudo apt install xscreensaver xscreensaver-data-extra

[edit: it looks like this version of bigscreen doesn't suport KDE login scripts so xscreensaver for now is a non-starter. Hopefully debian gets plasma 5.26 soon and this will then work]

[added:] Not quite full screen: KDE's window management isn't quite perfect, and full screen often falls short by 1 pixel on the right and bottom borders (despite any window rules you might add), this can be an irritant when a bright wallpaper sits behind whatever you're watching. Easiest fix is to set a dark-edged wallpaper. The newer bigscreen lets you use the kde settings which is nice as you can set the wallpaper to plain colour black, but the debian version you have to use the built in wallpaper settings app found in the settings menu on the home screen. It will only show you the wallpapers that are installed, so download your dark wallpaper, then move it to the wallpaper folder and it will show up in the wallpaper changer application:

sudo mv ~/Downloads/<wallpaper> /usr/share/wallpaper/
54
 
 

Had been waiting for my pi 5 argon case which got lost in the post before I could set this up. Ive been tinkering with an old SFF PC running arch over the last few months to get a "smart tv" set up going that im happy with, now ive condensed it down into a little debian box that uses a fraction of the electricity. Happy days.

55
56
 
 

cross-posted from: https://lemmy.world/post/11673921

I want to build my own portable E-Reader like a Tolino/Kindle in DIN-A5 format (I know there are similar projects, like the Open Book from joeycastillo, but I want to make my own just for fun). I'm considering using the Compute Module 4 from Raspberry Pi. That, at least according to my theories, would have the advantage of me not needing to create my own OS, and the availability of already existing EPUB/HTML (EPUB is essentially just HTML) & PDF parsers and UI libraries hopefully makes my life easier. I don't want to use a default Raspberry Pi, because I don't need all the ports and I want the size of the E-Reader to be not unnecessarily thick.

The modules I need/want:

  • Micro SD Card Reader for internal Storage (or just using eMMC Storage, have not settled yet on that topic)
  • SD Card Reader (large/normal sized SD Cards), with a snap-in/spring mechanism (like with Nintendo (3)DS cartridges)
  • E-Paper Display (e.g. a waveshare)
  • USB-C Port for charging the battery (and maybe, if possible also file transfer and if possible maybe also to connect to a docking station)
  • Battery

What is your experience with the Compute Module (4) and do you have good resources for creating my own PCB extension module for the Compute Module you would like to share? Do you have constructive critique for my project idea?

57
 
 

See title. I'm thinking of picking this up to power a pair of speakers but am currently powering my Pi using the GPIO pins. If I install this, will I no longer be able to power the Pi that way? Will I have to use the MicroUSB?

58
59
60
 
 

Hello, I’m starting a project to build something for a friends kid who’s father is a Huey pilot. I ordered the switch/panel in the image and want to 3d print an enclosure to mount it on that plays the song when the switch is in the on position.

Per the website the switch is fully functional, I just need to wire it to something to use it. Does anyone have suggestions on a bare bones controller to use and how to set it up to play an MP3 so long as the switch is in the on position? In a perfect world I would love for it to resume the position if it’s quickly toggled but restart if it sits more than a minute or so but realistically just playing the song would be more than enough.

While I’m new to Raspberry Pi I’m not that daunted by the task. I’ve been soldering since elementary school and have a degree in comp sci, but haven’t done any coding since graduating 10+ years ago. I do have a Pi hole but using an off the shelf package on a premade pi with step by step instructions doesn’t really count as “experience” for pi in my opinion.

Any suggestions are welcome, especially if someone can recommend some mini speakers that actually sound half decent. I’m not looking to tear a Bose Bluetooth apart but something slightly less tin-canny than a 2004 Nokia ringtone would be nice.

Thanks in advance!

61
 
 

Putting my #raspberrypi to good use by profiling my internet speed over the last six days. Looks like a seismometer at a System of a Down concert!

I am **not** very proficient in programming, but can someone please suggest some nice little projects like this for me, please?

@raspberrypi @raspberry_pi

62
 
 

Does anyone know of and can recommend something I can install that will give me stats like temperature, power consumption, memory utilisation and processor utilisation?

63
 
 

I have a TP-Link Deco X55 Pro Mesh home Wifi, and it offers an isloated Guest Wifi network. There is a single DHCP pool for both the main and guest networks, so the DNS servers set in DHCP have to be reachable from both the main and guest networks. If I simply connect the Pi to my main network, and set DHCP to use its IP as primary and 1.1.1.1 as secondary, then I have to go and disable all the secure DNS settings in Chrome and Firefox and Android or they all ignore my local Pi DNS and use 1.1.1.1. The guest network is wifi only, so I configured the Pi's wpa_supplicant to connect to the guest wifi SSID. The wlan is connected, but it's only reachable from devices on the main network (which it should not be), and not by other devices on the guest network (which it should be). All devices on the main network can reach the wired lan interface just fine, as the should.

I'm a bit confused about the state of wlan configuration though:

baron@pi-1:~ $ sudo wpa_cli status verbose
Selected interface 'p2p-dev-wlan0'
wpa_state=DISCONNECTED
p2p_device_address=da:3a:dd:c3:02:e0
address=da:3a:dd:c3:02:e0
uuid=ec1c452b-43b7-5991-b133-24ebb761a051
baron@pi-1:~ $ ifconfig wlan0
wlan0: flags=4163  mtu 1500
        inet 192.168.68.76  netmask 255.255.252.0  broadcast 192.168.71.255
        inet6 fe80::27a:d770:dd35:568f  prefixlen 64  scopeid 0x20
        ether d8:3a:dd:c3:02:e0  txqueuelen 1000  (Ethernet)
        RX packets 138327  bytes 10181404 (9.7 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1782  bytes 310865 (303.5 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

So even though my /etc/wpa_supplicant/wpa_supplicant.conf only has the SSID and PSK for the guest network, I can't actually confirm it via wpa_cli.

64
 
 

Still running pihole on the pi 3b+ after many years and was wondering about the above question since fiber is coming to my area soon ish.

From searches on Google it seems that it wont but what about if I start running other services on the pi? Such as VPN?

65
 
 

(Asking this here because r/raspberry_pi auto removed my post for not doing enough research and moderators haven't responded to my appeal.)

I have been trying to find out if I can use the fan & power button on this case with android as the operating system and I don't want to experiment on my own as I have next to zero knowledge on terminal commands.

The closest info I have found is this: https://gist.github.com/Lessica/30240b63ac0e47d80a919209ea006c60

But I looks like it only affects the fan, and I have no idea what I am supposed to do with this script in android anyways.

(info for my situation: I primarily use windows, and I would like to use android tv on my rpi4 with an argon one v2 case. I am open to using a linux distro if it's necessary to getting fan & power button scripts to work on android)

I do not know much about linux scripts and the only time i use them is when I am following a guide, so all results do not make much sense to me when I am trying to find answers. I also do not know how closely related Android is to linux so I do not know if I can just find a terminal app and enter the argon one script as is.

66
 
 

Title. In other words, sbc recommended/optimal power supply is 5V4A but I use an 5V3A instead -- will it damage or kill the sbc? The reasoning behind this is "an direct undervolting towards the system, for lower power draw and temps".

Thanks in advance.

67
 
 

Are there any major differences or pitfalls between writing software for the Raspberry Pi boards and similar SBCs such as the Orange and Rock Pi?

Such as:

GPIO and external Hardware Interaction

OS Integration: Challenges with different OS on various SBCs

I'm mainly asking about writing in Python

Thank you for reading and for any answers.

68
 
 

Im a first time pi owner, and I've run into an issue that I'd like to solve properly. When I first started playing around with pi os, Ubuntu, plasma, chrome, I ran into an issue where I could connect to my home wifi network, but get horrendous (30 to 78 B/s up and down), or no connectivity to the internet. No browser will connect to any site.

The pi os that came preloaded on a micro sd was hung up on some update that wouldn't go through. I decided to try a fresh rewrite of pi os , which was able to fully update without issue, and the internet connectivity issue vanished.

But has returned. Interestingly, using my phone as a tethered USB hub yields the same strangled up and down performance.

Does anyone have some ideas of how to identify what's allowing me to connect to my wifi network, or a tethered connection, while barely flickering in terms of upload and download speed?

69
 
 

Action Video

For her birthday my daughter received a cuckoo clock. It had very limited programming for 'quiet hours' so I fiddled with it and ended up breaking it. I didn't want to disappoint her so I gutted it and proceeded to install a Pi Zero W and a headphone amplifier I had built. She now has a fully programmable, USB powered, linux based cuckoo clock where I can program it to whatever suites our needs and it syncs it's time with NTP severs. I even connected her night light to it which turns on at night and off to let her know when its time to get out of bed. This combination also allows us to have dance parties with flashing lights, a dancing bird and fun songs coming out of her cuckoo clock. It's ridiculous and eccentric but it makes us happy!

Build

  • The Pi Zero's dont come with a sound output so I built an audio output filter to convert the PWM output to an analog audio output
  • Connected the analog out to a OPA1642 based headphone amplifier I designed and built
  • Wired up the cuckoo bird's coil actuator to a simple MOSFET drive circuit to control it from the Pi's weak GPIO output
  • Wired up some 5V string lights (used to be battery powered) to a simple MOSFET driver circuit to control it from the Pi's 3.3V GPIO output
  • Wrote some bash code to make the bird dance, the light flash and the cuckoo bird sounds play
  • All the scheduling and execution of the code is done clean and simple in crontab
  • I also have a text to speech engine verbally state the hour after the cuckoo action so my daughter can better learn to tell time by herself

To re-map the audio to the PWM0 output of the Pi

add to /boot/config.txt to remap the audio to the PWM0 and PWM1 pins of the pi.

# Enable audio (loads snd_bcm2835)
dtparam=audio=on
#remaps the audio to the PWM0 and PWM1 pins (pins 18 and 13)
dtoverlay=audremap,pins_18_19

Code

Cron Scheduling

@reboot /home/pi/startup.sh

#cuckoo between 8am and 6pm, inclusive
0 8-18 * * * /home/pi/cuckoo.sh

#turn on the night light at 6:15 pm
15 18 * * * echo "1" > /sys/class/gpio/gpio26/value
#turn off the night light at 6:15 am
15 6 * * * echo "0" > /sys/class/gpio/gpio26/value

Startup Configuration for GPIO

#!/bin/bash

#setup the GPIO
#"In order to use a GPIO pin through sysfs, we first have to “export” each one to make the appropriate paths available."
echo "17" > /sys/class/gpio/export
echo "26" > /sys/class/gpio/export
#set direction
echo "out" > /sys/class/gpio/gpio17/direction #cuckoo movement
echo "out" > /sys/class/gpio/gpio26/direction #nightlight

Flashing Light Code

#!/bin/bash

i=1

while [ "$i" -le 3 ]; do
        #turning the GPIO on
        echo "1" > /sys/class/gpio/gpio26/value
        sleep 0.050
        echo "0" > /sys/class/gpio/gpio26/value
        sleep 0.050
        i=$((i + 1))
done

Cuckoo Code

#!/bin/bash
i=1
echo "Looping "$(date +%I)" times"

while [ "$i" -le "$(date +%I)" ]; do
        aplay /home/pi/cuckoo.wav &amp;
        #flash the lights three times quickly
        /home/pi/flash.sh &amp;
        #turn on the cuckoo bird coil to make it bob down and flaps its wings
        echo "1" > /sys/class/gpio/gpio17/value
        sleep 0.300
        #turn off the cuckoo bird coil so it sits back down
        echo "0" > /sys/class/gpio/gpio17/value
        sleep 0.700
        i=$((i + 1))
done
#Text to speech engine, speaks the current hour through the speaker
#date + sed command below returns the hour, in 12 format, and the sed command removes the leading zeros
espeak -v mb-en1 -s 120 "it is $(date +%I | sed 's/^0*//') oh clock"
70
 
 

I've got a Raspberry Pi 5 which I've got set up and am slowly installing things on via Docker Compose, but I've realised that I'm unable to copy or even highlight text. It's like there's a phantom click or something. The mouse works on my other laptop, but that's got its own problems. Anyone know how to fix it?

71
 
 

I was looking through the docs and forum posts and it didn't mention anything useful, just that you can.

72
73
 
 

Is there any difference from one another? I keep hearing that using chargers is absolutely a no-go and that power supplies are much safer and better overall. Do you guys confirm this?

Thanks in advance.

74
0
submitted 1 year ago* (last edited 1 year ago) by SonyJunkie@lemmy.world to c/raspberrypi@lemmy.ml
 
 

I'm fortunate to live in Cambridge so my wife popped in to the store and picked one up for me. I forgot to ask her to get a case so that's an excuse to go back over the weekend 🤣

75
 
 

Clever little Python tool provides a constantly-updated text-based user interface (TUI) for GPIO pin status, by querying the RP1 chip.

view more: ‹ prev next ›