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30

The Raspberry Pi 2 will give BCM2709 hardware and ~1 GB of RAM like this: pi@raspberrypi:~ $ cat /proc/cpuinfo | grep Hardware Hardware : BCM2709 pi@raspberrypi:~ $ cat /proc/meminfo | grep MemTotal MemTotal: 947756 kB while the Pi 1 reports BCM2708 hardware and definitely less than 1 GB: pi@raspberrypi:~ $ cat /proc/cpuinfo | grep Hardware ...


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. ...


29

No. There is no method by which RAM can be added to the Pi. See this discussion on the raspberrypi.org forums for more details, but basically the RAM and CPU are inextricably, inaccessibly connected. There is no physical method by which RAM could usefully be added, unless you want to start acid stripping the CPU chip, getting your microscope out and tracking ...


29

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


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 ...


25

I've got a couple of Pis running my Ham Radio repeater and irrigation system - realistically, I'm rebooting them maybe once every 6 months for security updates or some other "maintenance" reason; but I've not seen issues where a reboot was REQUIRED to "keep things running"


25

In terms of hardware, the only reason you should ever need to reboot an ARMHF-y board is firmware changes, necessary changes to ROM, or possibly new devices that must be present at boot. For instance, adding a driver or close-to-metal kernel module and a device implementing that driver will probably need a reboot, just to tell the CPU and kernel memory ...


23

The general consensus is that clusters are a waste of bandwidth. Yes, your cluster will have access to the sum of all the processing power and RAM, but you are introducing network latency into your performance equation. If you are focused more on RAM than CPU, you could build a RAM-heavy desktop for the same price as your Pi cluster. You mentioned 20 Rpi2 ...


22

If you don't want to click links, the Raspberry Pi can handle 4.75v to 5.25v. As for the current draw/power consumption, here are some numbers: All of these are bare-bone (does not have any peripherals/accessories attached) *** Fun Fact (Tested on Pi1 B+) *** Any turned-off Raspberry Pi that's still plugged in: 75 mA *** Idle *** Raspberry Pi 2 B: ...


21

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 ...


20

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.


18

From Raspberry Pi 2 - FAQ and collated answers Do I still need CODEC licences? Yes, if you want to use the HW decoders. However, the higher speed of the device MIGHT mean a SW decoder can be used. This will depend on the resolution of the video you are trying to display.


18

I just had this same problem. Here is what eventually worked after reading this (From the comments it looks like you had the same issue as I did): vcgencmd get_camera (Returned supported=1 detected=0) Check to make sure ribbon was facing the right way (it was) Check to make sure ribbon is all the way in the connector slot (it was) Check to make sure ribbon ...


17

The B+ had a single core Broadcom BCM2835 Arm 6, with 512MB of RAM. the Raspberry Pi 2 (is newer) has a quad core BCM2836 Arm 7, with 1GB of RAM. As a result of the quad core CPU the Raspberry Pi 2 has a higher current draw. Adafruit put together a nice comparison of the two, that includes a section detailing how to tell them apart.


15

Ensure terminal over serial is disabled in raspi-config Run sudo raspi-config and in "Advanced" choose "Serial" (Enable/Disable shell and kernel messages on the serial connection) and disable it. Steps 2 and 3 should not be necessary if you do this step first, but in case it didn't work - check them also. Ensure /boot/cmdline.txt has no ttyAMA0 The ...


14

The community is in the progress of making dotnet core working on ARM. Samsung recently joined the dotnet foundation to (mostly) do work for ARM. .NET is a great technology that dramatically boosts developer productivity. Samsung has been contributing to .NET Core on GitHub – especially in the area of ARM support – and we are looking forward to ...


14

Raspbian by default is configured so that the root account can't be logged into using a password. This is done by starting with an entry in /etc/password which begins: root:x:0:0: The fields are separated by colons and explained in man 5 passwd (note the 5, since man passwd will give you the man page for the command passwd; section 5 is for configuration ...


13

[There is now a Fedora aarch64 release for the Pi 3, and on the same page an armv7 for the 2/3. I'm leaving this answer as is though, since it can be applied to any generic GNU/Linux ARM distribution.] Yep, Fedora 21 [and more recently, 23...27] works. However, the pi 2 still requires a special out-of-tree kernel, and you need the firmware and bootloader, ...


13

The Raspberry Pi requires 5 Volts - if you've fed it 12 Volts you've killed it. Powering the Pi using the GPIO pins bypasses the fuses that might have saved the Pi if you had used the micro USB connector. If smoke came out - you've provided too much power to the Pi somehow. That board appears to be designed for an Arduino which has 5V outputs, the Pi's GPIO ...


12

I believe the tape is useful for manufacturing using a vacuum based pick and place machine. The machine can't pick the parts up if they're full of holes. Removing it shouldn't do any harm.


12

No. Generally each Pi model has already been fitted with the maximum amount of RAM supported. Some early model B's only had 256MB and could have had 512MB instead. However there would be no way to update the RAM chip without destroying the board (unless you had a special laboratory).


12

This pin is directly connected to the 5V net, meaning indeed it is possible to power through that pin. When under USB power, this net is supplied by USB power, but there is no reason you couldn't power it yourself, however, replicating some of the protection scheme is worthwhile to protect power supplies and prevent fires. In my opinion, modifying the ...


11

There is no official library There are several options. I usually use http://wiringpi.com. This is used for the gpio utility included in recent Raspbian releases. Joan's pigpio library is at https://github.com/joan2937/pigpio and she also has Python wrappers. If you want to use sockets or a daemon this is recommended and has good support for hardware and ...


11

'Mono' is a toolset and C# used to create “.NET” compatible programs based on Linux, and the resulting binaries are fully compatible with Microsoft.NET. start from the Basic programs given in the link here which will definitely help you to understand ´mono´ better. In Addition I have also used the documentation from the mono developers this which was very ...


10

tl;dr Most likely the Pi is routing the audio through the HDMI port, run the following command to make it use the 3.5mm plug output: amixer cset name='PCM Playback Route' 1 more detailed answer Out of the box, the Pi has 2 audio sinks or outputs: HDMI and the 3.5mm plug, if a display is connected the Pi defaults to using HDMI audio. You can change the ...


10

I think you need to clarify what you are trying to achieve, but hopefully this will help. Firstly, C# is a language. You write programs in C# and these will run on the .NET framework. It is the .NET framework that must be installed on your device for your C# program to run. Since last year you have the option to install Windows 10 IoT Core on your ...


10

The manufacture of Raspberry Pi's as far as I am aware is by Element14/Premier Farnell. Originally they were made in China but are now produced in the UK, which is fitting, given the Foundation is a British organisation. You can read more about that here. In terms of a Pi made for commercial use Element14 have an exclusive Raspberry Pi customization area. ...


9

Your program is stuck because you have made an infinite loop in it. By the time you get to the while(sw1_status != 0) line, sw1_status is guaranteed to be True, and True != 0 will always evaluate to True. Perhaps you meant to wait until the button is released, in which case you want to update sw1_status in the loop, by replacing pass with sw1_status = GPIO....


9

The Pi has a 30-bit (1024MB) address space (the top two bits are used for caching aliases). A small amount of one of the aliases is used for gpu peripheral access. The arm accesses gpu memory space through a coarse MMU that allows 64 blocks of 16M to be mapped in. On Pi0/Pi1 we use 32 of these blocks to access 512M of sdram and one block for gpu peripherals....


8

The batteries won't force current through the system. Your bigger problem, though, will be running the Raspberry Pi 2 at all on 4.8 V. It's very close to under-voltage warning (which I saw quoted as 4.65V for the B+). You'll need some kind of DC-DC converter to get the voltage to consistently ≥5V.


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