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5

Check your program is actually multi-threaded enough to run in parallel. (Also you shouldn't need the sudo - IIRC systemd will run your command as root by default)


4

The Pi has 3 "components" the CPU, GPIO and Video Core which are relatively independent. Even when the Pi is shutdown the Video Core continues to run, and the GPIO pins retain their state; only the CPU is not running. (All Pi models before the Pi4 have identical GPIO and Video Core; only the CPU changed on the Pi2 and the Pi3. The Pi4 is all new.) ...


3

When will Pi4 officially support this feature? Since 2020-06-15 Is the beta bootloader safe to use? The beta bootloader is promoted to be stable (see link above). So it should be safe to use. How to use the beta bootloader? Have a look at Pi 4 Bootloader Configuration


3

You can use dd, this applies also for creating an image of an SDD, USB, ... and restoring it It's best to unmount the drive you're going to copy. In case of the SD-card, remove the SD-card from the RPi and put it into a card reader. Don't mount. The basic command is this: dd if=input_file of=output_file status=progress Use lsblk to determine the name of the ...


2

I would put an ESP32 or similar in between to Pi and HX711. You could build some functions (e.g. tare) into the Arduino so it closer to the weigh scales than the Pi so you can check the device. Note load cells can drift over time if constantly under load so you may need to introduce check and calibration processes. The HX711 has an Arduino library that ...


2

It appears apt-get install --reinstall raspberrypi-bootloader\* raspberrypi-kernel\* is the solution.


2

Have a look through Using rsync to backup Pi You need to set the exclusions to include where the roms are stored. I would question why not backup the rom files though? Restoring the machine WHEN (not if) the SD card fails will take significantly longer if you have to download / find all the rom files again...


2

Using Andbdrew's tips above I was able to make this work headless (and with a head) consistently without disabling Cloud-Init. Thanks to @enconn, for brainstorming and a link to https://cloudinit.readthedocs.io/en/latest/topics/examples.html#reboot-poweroff-when-finished. Image the SD Card using Raspberry Pi Imager v 1.3 selecting the 'UNBUNTU 20.04 LTS (...


2

There is an image which shows default pullup (among other things) http://www.panu.it/raspberry/ NOTE the above is not strictly correct for the Pi4. The Pi4 default pin settings (and most common optional settings) are identical, but the Pi4 has additional settings for some pins. See Pi4 GPIO The BCM2711 ARM Peripherals which can be downloaded is the ...


2

Yes - it will work. UNLESS: The only thing you should be aware of is the possibility that your Huawei charger uses an e-Marked cable. The e-Marked cable will be a problem IFF you have one of the "first-run" RPi 4s, this because the Raspberry Pi Organization built thousands of units with a design flaw. The design flaw has now been recognized & ...


2

Just append to /boot/cmdline.txt quiet plymouth.ignore-serial-consoles This should suppress all console output and only present you the login prompt.


2

With the introduction of v5 lots of things have changed as the developers have moved from flat files to using a database and not all things have a gui or command line process yet. As such I would: Log into your pi-hole admin console Add a single black list entry Go to Settings / Teleporter and export all files Unzip the files and look at the blacklist ...


2

Jenkins and Maven by themselves don't consume any significant CPU time. You need to profile specific implementations of the compilers you're going to use. If you're interested in GCC and don't have a Pi for a test, I can tell you that building the Pale Moon browser on a Pi 4 takes a bit more than 3 hours, vs. 30 minutes on an i7.


2

I would refute the car damaging phone batteries as I used to look after over 100 mobiles and the most damage was from drops. In 6 or so years we may have had one or two dead units from battery failure. The general chargers you buy (normally cheap) are very poor and can drop voltage down by 1-2volts under low load. As for running the Pi I would look to ...


2

check HDMI cable set hdmi_safe=1 try set parameters hdmi_group and hdmi_mode for your display (watch next point) read this link


1

All sorts of circuitry will be powered while power is applied even after you shut down the operating system. You would have to study the schematics for your Pi model to check which components are still powered. I think early Pi's still used about 100 mA at 5V when shutdown.


1

The most helpful link on that I found is this one: https://business.tutsplus.com/tutorials/controlling-dc-motors-using-python-with-a-raspberry-pi--cms-20051. The diagram below shows essentially how the L293D works: However, I strongly recommend you use an L298 motor driver instead because the amps out for the L293D is maxed at 600mA (the stall current is ...


1

It will not work. The Pi's aux SPI device only works in modes 0 and 2.


1

Turns out an audio jack has to be connected when the python script is running in order for the USB sound card to be working. Strange, but works for what I'm trying to do. When configured to use the internal 3.5 mm minijack port this is not needed.


1

You should never run a Pi from a charger. It is feasible for the charger to drop the voltage to below the working limits of the Pi as the current requirement increases. They also suffer from small voltage drops randomly unless they are of good quality. You would do much better to get a decent 5v power supply or use the 5v output from a PC power supply and ...


1

Does you monitor actually have speakers? I have a number of Acer monitors; of those one has an HDMI input but no speakers and there is no volume control in the settings.


1

Please note that pi-hole is not Pi specific and you may do better on their ‘discourse’ server. The entry is due to the router itself not using pi-hole for DNS not devices connected to it. Unless the router needs to perform automatic updates (EE routers for example in the UK) then it is very very unlikely a home router would need to use pi-hole as it does not ...


1

I found out that adding more GPU Memory helps! I can't overclock it more that I already have, but setting GPU memory to 460 seems to improve performance.


1

A minimum supply of %V 2.5A will work. So you can use that charger/adapter. But use your equipment carefully. If anything pulls current more than it needs the system will fry.


1

I found out that my wlan0 was disconnecting due to country mismatch on a router and board itself. Once I set them both to matching, disconnects vanished. Router setup: And wpa supplicant config: country=NL ap_scan=1 passive_scan=1 network={ ... }


1

You can overcome the GIL limitation. The details are here and too long to copy into this post. The technology relies upon compiling some forms of Python code using the Just In Time compiler Numba. In general compiled code called by the Python interpreter can release the GIL and execute on multiple threads at the same time. Libraries like NumPy and Pandas ...


1

According to the Debian Wiki it could be possible, because RPi4 now boots from CPU instead of GPU. Unfortunately, it seems that currently the Debian kernel does not support the RPi4. Sources: https://wiki.debian.org/RaspberryPi#Raspberry_Pi_4


1

it seems there is a problem to coordinate all the additional helpers. But there is an easy way to just configure the Raspberry Pi OS with no need to install additional programs. You can use systemd-networkd to do all things. It has all needed features built-in. You just configure it, what make thinks lean and well-arranged. You can look at Access point as ...


1

Happy to say that the problem turned out not to be the panel mount adapter, but the micro-HDMI adapter I was using. If anyone stumbles on this issue, make sure you're using a good one!


1

Some useful commands to get more debug information from the system are: Have the bluetoothctl tool running in a different terminal when you are running your commands and it may give you more information More detailed bluetooth information can be found with sudo btmon -t |& tee ~/btmon.log DBus debug information is available with dbus-monitor --system


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