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282

To completely disable the onboard WiFi from the firmware on the Pi3 / Pi4, add dtoverlay=disable-wifi in /boot/config.txt. This is documented here. Please be sure to use an up to date firmware, this feature was added in January 2017. There is also an overlay for disabling onboard bluetooth : disable-bt. If you want to disable both wifi and bluetooth, ...


69

cat /proc/device-tree/model returns something like Raspberry Pi 3 Model B Rev 1.2


67

This answer is still correct, and explains in more detail the nature of the changes, but most users of current Raspbian should just run sudo raspi-config Select Interfacing Options / Serial then specify if you want a Serial console (probably no) then if you want the Serial Port hardware enabled (probably yes). Then use /dev/serial0 in any code which accesses ...


58

One of my friends had the very same error which he resolved by following the steps on this page. Apparently there is a/are defect(s) which prevent xrdp working with the vncserver. However it works with tightvncserver Also the order of installation of tightvncserver and xrdp seems to be important. In summary remove the following packages : xrdp, ...


45

See Ludovic Ronsin's answer below about using dtoverlay, a method added in January 2017. This post seems to be talking about this. The answer talks about disabling the drivers by editing the file /etc/modprobe.d/raspi-blacklist.conf and adding: blacklist brcmfmac blacklist brcmutil Alternatively, you could use crontab -e and add: @reboot sudo ifdown wlan0 ...


39

The network module is a a BCM43438. I'm having trouble finding a source I fully trust, but from a cursory view, it looks like it only supports 2.4 GHz. Since the Raspberry Pi foundation doesn't specify, it'd be normal to assume a lack of 5 GHz. An image on raspi.tv displays a very compact antenna. Reception with the default antenna may not be stellar, but ...


37

How do I update my RPi3 to Python 3.6? As of today, only the installation from source is available. The instructions you referenced are correct for version 3.6. To repeat: wget https://www.python.org/ftp/python/3.6.0/Python-3.6.0.tgz tar xzvf Python-3.6.0.tgz cd Python-3.6.0/ ./configure make -j4 sudo make install On a fresh Raspbian on Raspberry Pi 3 ...


32

Since you are running with Jessie, you are supposed to define the hardware in /boot/config.txt (Reference to overlays for pi). Disable Bluetooth and WiFi by adding the lines dtoverlay=pi3-disable-bt dtoverlay=pi3-disable-wifi Optionally you might also disable the following service sudo systemctl disable hciuart See also the following discussion on ...


31

You can use sudo iwconfig wlan0 txpower off This should disable the wifi adapter. Use sudo iwconfig wlan0 txpower on to enable it again. Reference: https://manpages.debian.org/buster/wireless-tools/iwconfig.8.en.html


29

There's a short piece that includes Pi 3 benchmarks over at the PiMoroni blog. All of the benchmarks below were carried out with just a USB keyboard and mouse connected with power supplied from the official Raspberry Pi Power Supply, with the exception of the WiFi dongle test in which the USB WiFi dongle was also connected. The Pis were naked, i.e. ...


28

It's in the raspberrypi.org repository for Raspbian now. sudo apt-get install chromium-browser


28

I highly recommend you check out the Berryconda package manager by jjhelmus. It is basically a more up-to-date version of the armv7l version of Miniconda, and has the Python 3.6 package available without needing to compile it from source. Alternatively, if you already have conda installed, you can try just simply adding Berryconda's default rpi channel and ...


27

When shutting down the HDMI and USB on the Pi3, the current drops to 160 milliAmps. In my tests, this was roughly 200 milliAmps on the Pi2. Thus, shutting down hardware (if you don't need it), can be a huge energy saver. Update: Use this command to turn HDMI off: /opt/vc/bin/tvservice -o And this command to turn it on: /opt/vc/bin/tvservice -p Use this ...


27

While the processor in the Pi 3 is 64bit. The new chip is fully backward compatable and it uses the same 32bit OS, hence all programs will continue to work. Additional information can be found in this question.


26

The APX803 chip (which monitors voltage) triggers at 4.63±0.07V. This is an instantaneous level, whereas your meter will show average. Even assuming your meter is correctly calibrated the trigger may fire if the load varies. The visual trigger has a 3 sec so it will show even if the average is 4.75V (which is already at the lower end of the tolerance range)....


26

No, you should not increase the voltage any further... and at least this answer linked in the question does not suggest to do that. From Raspberry Pi Power Limitations: Power sources SHOULD provide 5±0.25V ... and: The newer Pi(3/2/B+) have a voltage monitor chip (APX803) which triggers at 4.63±0.07V. The Pi3B+ uses a MxL7704 chip to manage power, ...


24

According to this the required pin(s) on the BCM43438 were not easy to route out, and so are not connected on the chip.


23

This answer is outdated and should no more be followed. See https://raspberrypi.stackexchange.com/a/56231/42933 for—since October 2016—the most appropriate answer. As already shown in the previous answer, the general idea is to use Chromium builds from Ubuntu. Using their staging repository for Chromium security updates is probably not the only way, but not ...


23

First of all, repeat following process sudo apt-get install python-pip pip freeze | grep RPi see what you get after this second command, If you get a valid module for RPi.GPIO or not. And then following if not installed. For Python 2 sudo apt-get install python-dev python-rpi.gpio or pip install RPi.GPIO For python3 sudo apt-get install python3-dev ...


22

Here are some suggestions. Use the raspi-config utility to reset the timezone even if already you used a different tool to set it. sudo raspi-config Manually set the time to be somewhat accurate. NTP sometimes won't update if the time/date is wildly wrong. sudo date -s "01/04/2017 11:00" Manually force time update: sudo systemctl stop ntp.service sudo ...


22

By CPU Type You could check the RPi version with the command, uname. The different RPi versions have different CPU architectures. The RPi 2 has an arm7, whereas the 3 has an arm8. uname -m By Hardware Revision If you need to be more specific, you can check the revision entry from the output of cat /proc/cpuinfo. If you want to just exact the revision ...


22

By default, any computer will try to use all of its cores when it can. However, it can only achieve this when an application is multi-threaded. If it is not (i.e. a Python script that doesn't use the threading module), then it can only use at maximum, one core. This equates to 25% of the CPU on a four-core CPU. If you'd like to modify your script to use ...


21

Yes, it can be done, but beware of violating FCC. Details here: External antenna modifications for the Raspberry Pi 3


21

The Rpi logo used with the default kernel replaces the normal Linux penguin(s). These indicate the number of processor cores detected by the kernel, hence on a Pi 2 or 3 there are 4.


20

finally this got work for my pi3 (os: debian jessie) please follow these 6 steps carefully. Step 1 - Install Raspbian Jessie onto a SD card and boot the Pi when connected to a network Login via terminal or desktop and shell Configure the system with: sudo raspi-config Expand filesystem and enable serial on advanced page, exit and reboot. Step 2 -this ...


20

The Pi has no inbuilt current or voltage sensors which could be used for monitoring its own current draw, or a battery supply. You will need to track down a multimeter or other measuring device (this type of thing is very common) to keep track of your power consumption.


19

Ok so I've done some more digging and several more hours of experimenting, and here's a more thorough answer, including info on how to get xrdp remote sessions to have the nice mouse cursor again instead of the big "X". Background info: It appears to me that Raspberry Pi 3 is the first Pi to come pre-installed with RealVNC, and RealVNC interferes with xrdp,...


18

The best information I can find suggests that it's possible to output 4K resolutions, but at fairly miserable frame rates. The Pi 3 has the same GPU as the Pi 2, so the information should still be valid: Source: https://www.raspberrypi.org/forums/viewtopic.php?f=38&t=79330 I have managed to get 3840 x 2160 (4k x 2k) at 15Hz on a Seiki E50UY04 ...


18

There seems to be Raspberry PI support in the pfsense github repository. See pfsense repository. For raspBSD see RaspBSD. It seems feasible to compile pfSense for the Raspberry PI. I think it would be a useful port to have for people that don't require a lot of bandwidth or want to implement their own cheap WIFI router. And it would be interesting to play ...


17

The Pi 3, while idling, consumes about 220 mA. Under loads, it is known to reach up to 1 A, and with USB devices plugged in, it can reach 2.5 A. There is no on board current sensor, so this is only a tool for a good estimate.


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