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Based on the answer by Ingo, I went and made a script to do this job. https://github.com/Autodrop3d/raspiApWlanScripts The gist is that there's one script to run that'll setup the Pi for reboot-less AP/STA switching and then there are helper scripts that'll actually do the switching for you.


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Since all RPi use b8:27:eb as the first three octets of their MAC address, you can use arp from your Mac/Linux PC, but you'll need to refresh the arp cache first. Here's a bash script that will do the job. You can get more details from my github page on the subject. #!/bin/sh : ${1?"Usage: $0 ip subnet to scan. eg '192.168.1.'"} subnet=$1 for addr in `...


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For anyone having the same issues: It turns out that the above code uses too little CPU load and therefore does not shoot up the frequency. When I checked, my CPU was constantly running at 700 Hz. To achieve the required FPS on the above resolution, I changed my cpufreq governor from ondemand to performance. This might not be the only or the best solution, ...


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You can use a few different tools like nmap and other mapping tools. But i would reccomend to use angry ip scanner as it's very simple to use.


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As you are told by systemd: zfs-import.service is not a native service, redirecting to systemd-sysv-install. Old style SysV init system is deprecated and not used anymore. For compatibility it is only emulated by systemd but there are limitations. Look at Compatibility with SysV. If you encounter problems with SysV emulation then the first step should ...


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As joan pointed out in the comments above, there were extra spaces after "Keycard"


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The error generally means that you have called a function that does not have a prototype. In this case I think you mistyped the function, capitalizing the 'L' where you should have lower case 'l'. Note the difference between the one that you commented out and the ones that follow, copying from your code in the question: //bcm2835_gpio_fsel(uint8_t pin, ...


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playsound uses Gstreamer library for playback, which should normally rely on PulseAudio (although other plugins do exist) using the default audio sink. I would start by running pavucontrol and check that the A/V port is selected as default audio sink, and set it as default if it isn't. This question has an answer with a much more detailed troubleshooting ...


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I found this is the bug in Raspbian kernel. https://github.com/raspberrypi/firmware/issues/1005


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I can confirm, after having used the Bela shield on top of a Beaglebone Black, that its latency is extremely low (<1ms) and quite capable of doing calculations on audio. The normal shield has 2 jack microphone inputs and 1 jack stereo output. Strictly speaking, you have to buy the version that comes with jack adapters, though. I do believe more inputs/...


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The value 1437495737 is in hex 55ae71b9, or in little endian notation b9 71 ae 55 while the integers 185 113 174 85 are in hex also b9 71 ae 55. So you get the same value, just in different representation.


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TL;DR The external hard drive is powering the RPI after you remove the microUSB power supply. This is called Backfeeding. This is not unusual for raspberry pi's. Is it bad for the pi I would advise against backfeeding because there is little protection for the Pi. You would need to ensure there is a stable voltage and current to avoid damage. I would ...


1

As you have noted GPIO pins retain their state when shutdown. There are a couple of exceptions where the state is modified by the shutdown process. gpio-poweroff (which is designed for this purpose) is the most reliable method. See https://raspberrypi.stackexchange.com/a/94399/8697 PS RUN and EN pins are INPUTS, and NOT connected to the GPIO. RUN is ...


1

If the drive is supplying 5V power to the USB port, it will power the Pi. As this is unusual, and not complying with the USB spec, no one can say if it is safe. NOTE You can not power a Pi through its USB ports, although once booted it will continue to run.


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This howchoo post shows how to connect an LED to show the status of the Pi. The LED is steady on when the Pi is running, and off after shutdown. Briefly: Add this line to /boot/config.txt, and reboot enable_uart=1 Connect the TxD pin (GPIO pin 8) to the positive lead of a 2 or 3 volt LED. Connect a ground pin (e.g. GPIO pin 6) to a 330 ohm ...


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This answer on Unix Stack Exchange helped me. I needed to open ~/.config/chromium/Default/Preferences and add a window_placement key under browser containing: "window_placement": { "bottom": 800, "docked": false, "left": 0, "maximized": true, "right": 480, "top": 0 }


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the solution is to use orange pi r1, only available on aliexpress (yes it is Chinese) it have 2 Ethernet sockets which you can bridge and put your code in between, now how to bridge this guy, sorry i am the wrong man. also note that this board is not heavily documented nor super user friendly (watch youtube reviews) so you might do a long journey, hope ...


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There are several possibilities to configure a Raspberry Pi to be "a man in the middle" (a very common hacking issue). Because I don't know what do you exactly want to achieve, I will show a simple configuration with a bridge. This is completely transparent to the PS4 but you are able to monitor any traffic of it. Of course you need an additional USB to ...


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I found one not very good solution, which is suitable to my problem for now. I managed to output the whole video signal (not only the camera video) via 3.5mm TV output. Then I ran a script to make the camera video full screen, and got the camera video on the receiver screen.


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PiCorePlayer to the rescue. For now, I'm using a dedicated 3B+ as music server running piCorePlayer serving music via BlueTooth to either a BT speaker (UE Boom 2) or Logitech BT audio adapter which feeds my stereo. The BT connection runs in 'beta' mode, so it may not be fully baked yet. I do find that to change speakers, I have to reboot to complete the ...


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Question I wrote a script using GPIO pins and I'm fairly certain there was no way for it to cause a short circuit. Answer Well, if you are connecting a GPIO pin to any pin of a 5V powered device, then there is risk of frying the Rpi or shortening it life。 You might like to read the following posts for more details. DHT11 sensor and the wrong ...


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If there is no 3.3V the Pi is DEAD! No script can damage the Pi (although it can corrupt the OS - as can pulling the plug). NOTE poking a voltmeter at the header pins is a BAD idea. Even it the Pi wasn't dead, a momentary short between the 3.3V & 5V pins (which are adjacent) is invariably fatal.


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You installed the tor service that can only be used by applications directly. At the tor project you will find at Configure your applications to use Tor: If you want to use Tor for anonymous web browsing, please use Tor Browser. It comes with readily configured Tor and a browser patched for better anonymity. To use SOCKS directly (for instant messaging, ...


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It is exactly determined what the Raspberry Pi 3B+ is able to do with its WiFi on-board device. With the command iw you can show what interface combinations are possible. Just execute $ sudo iw list | grep -A4 "valid interface combinations:" valid interface combinations: * #{ managed } <= 1, #{ P2P-device } <= 1, #{ P2P-client, ...


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I know the OP is almost one year old but I found the OP very interesting and did some research. The Raspberry PI 3B+ uses Cypress SoC CYW43455 for wifi and Bluetooth. The specs of the SoC are impressive but as XTL mentioned earlier this chipset does not support real simultaneous dual-band (RSDB). This is confirmed on this post in Cypress Developer Community. ...


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You can solve this by rolling back to the previous verified version, as the latest install.sh file seems to be causing this issue. Try changing your install_respeaker.sh file to the following: #!/bin/bash sudo apt-get update sudo apt-get upgrade git clone https://github.com/respeaker/seeed-voicecard.git cd seeed-voicecard git checkout ...


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Question Power 2 Rsp3b+ via a Power USB hub [powered by 12VDC 2A, 24W wall wart] Will blow or burn Pi's due to over voltage? Answer Well it is 90% likely (but no guarantee!) that everything should go well, if you use the "[2.4A] Intelligent charging" and "[2.4A] Quick charging" ports, one for each Rpi. References Amazon 24W 6-Port USB Hub, ...


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You can not power a Pi reliably from a hub! The USB3 fast change ONLY works with phones which support and can negotiate the protocol - the Pi CAN’T because it doesn’t even have data lines on the power port.


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USB is a standard and must have 5V. The 12V you mention are the output ratings for the HUB's power supply. To be compatible with USB there must be an additional DCDC converter inside the HUB. Whether this HUB is capable of driving 2 RPis or not depends on the current it can provide, not its output voltage. A voltage of ~5.5V must not be exceeded! Note that ...


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What do you mean by image is corrupted ? If it's an installation issue with WIn32DiskImager, here's my experience: I just installed Raspbian on an SD Card this morning and I got an error too but went to Raspbian official doc and found Etcher which work really well and even have a portable version ! Here's the release page of their Github, you'll find what ...


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Question SparkX VCNL4040 proximity sensor module No clue on build or use build Still have to install circuitPython bundle Answer SparkX is a cousin of SparkFun. You can usually find newbie friendly hookup guide from SparkFun. It might be hard to build the driver yourself, because Rpi stretch is not that compatible to old jessie. ...


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I assume you are running Raspbian Stretch. If so you can use systemd to try to boot into rescue or emergency mode. In systemd.special — Special systemd units you will find for rescue.target A special target unit that pulls in the base system (including system mounts) and spawns a rescue shell. Isolate to this target in order to administer the system ...


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Question How to connect Rpi to 50 microphones? How to store a few seconds of analog audio signal on the SD card? Need a multiplexer? if so, how many? Short Answer A quick and dirty hobbyist DIY wiring is to connect the 50 microphones to a structured/layered multiplexer/dimultiplexer of analog switches. You can use an Analog To Digital ...


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Question Rpi can no longer boot after installing wrong LCD driver. How to fix? Answer Short answer A quick and dirty fix is: Use a new SD card with a freshly downloaded Raspbian image, without any new LCD driver installed. Then install your correct LCD driver. Long answer You can fiddle with the Raspbian config files to remove wrongly ...


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It doesn't look like an overly complicated sensor. If you can write a program you should be able to talk to the sensor with quite simple code. It should appear on the I2C bus at address 0x60. i2cdetect - y 1 You can talk to the device with Python via the standard SMBus module. If you don't know how to or don't want to program your options are more ...


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Question Two identical Rpi3B+ setups, "good" setup boots SD Card OK. The "bad" setup can only start booting to 4 green LED blinks, then stops. Why? Answer I suspected your PSU is marginal, and when booting, drops to a low voltage much below 5V, and so any weird thing can happen. So I tried using a adjustable PSU and see if Rpi can boot at a ...


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