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63

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 ...


18

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 ...


14

I've made this answer to summarize the experience to this issue. We are talking about Raspberry Pi 3 Model B+, released on 2018-03-14. It has some new and updated features compared to Raspberry Pi 3 Model B. A 1.4GHz 64-bit quad-core ARM Cortex-A53 CPU Dual-band 802.11ac wireless LAN and Bluetooth 4.2 Faster Ethernet (Gigabit Ethernet over USB 2.0), maximum ...


11

It's really advisable to upgrade to stretch, but if you want/need to stay with Jessie, follow these steps to get it working: You'll need to do this first step on a pi3 (not plus): Update the bootloader: sudo rpi-update ef7621d91cb58ccc856c3c17ddda28685edd23f3 After that the card will then boot on pi 3B+, but without WiFi Download and install the new ...


9

Quite simply, extra power. The lightning symbol means the pi isn't getting enough power so try another power source preferably one rated at least 2.5A. The model B+ has slightly more power requirements and it will be especially noticeable if you are also trying to power USB devices like an external HDD. Also make sure your firmware on the SD card is up to ...


9

We are talking about an access point together with a wlan0 client connection to another wifi network (wlan repeater) or an internet router. If you want an access point together with an ethernet port eth0 as uplink to a switch or an internet router then look at Setting up a Raspberry Pi as an access point - the easy way. The Raspberry Pi is able to work as ...


8

Naseer's answer is correct but a bit elaborate if you just flashed the latest rasbian. All I needed to do, is just to add the following line to my config.txt (from e.g. windows where you plug in the SD card on the fat32 partition): dtoverlay=pi3-disable-bt Then plug it in, and the pi will directly print stuff on the console pins.


6

Testing points on a Raspberry Pi 3B and 3B+: PP1 VCC +5V (from micro USB receptacle) PP2 VCC +5V (from micro USB receptacle) PP3 GND PP4 GND PP5 GND PP6 GND PP7 5V after polyfuse PP8 3V3 PP9 1V8 PP10 Power LED PP11 PP12 PP13 Status ACT LED PP20 H5V (5V at HDMI connector) PP21 RUN (reset signal) PP22 Ethernet Activity LED PP23 ...


5

Powerbanks are not made for powering electronics. They are made for re-charging batteries. This is important because these two tasks have some requirements that are at odds. Most significantly, in powering electronics it necessary for the supply to be responsive to rapid fluctuations in current draw, but the exact opposite is true with regard to ...


5

network-online.target is a static unit. You can check it with: rpi ~$ systemctl list-unit-files network-online.target UNIT FILE STATE network-online.target static 1 unit files listed. means it has no [Install] section and starts only if it is Wants or Requires by another unit. It cannot be started and stopped and does not run on bootup. But if ...


5

I have found that it is better to use wlan0 as interface for the access point and wlan1 as client up-link. But this other way around does not answer the question. So I have made a new question Access point as WiFi repeater with additional WiFi-dongle. Look there for an up to date configuration. This answer here will not maintained anymore. The real issue ...


5

Linear for the win! y = (slope * x) + intercept is the classic linear formula, in your case, x=sensor, y=bars, so the formula becomes bars = (slope * sensor) + intercept ... and you have two data points of this formula, sensor@750, and sensor@3750 equation 1: 0 = (slope * 750) + intercept equation 2: 250 = (slope * 3750) + intercept ... lets rearrange ...


5

I have powered green, red, yellow, and multi-colored LEDs direct from the (3V3) GPIO. So a green LED forward voltage of 3V3 seems unlikely. Anyhow putting 20mA through a modern LED would be absurdly bright. Try something in the range 300-500 ohms (or higher) and use PWM on the GPIO to vary the brightness if needed.


5

You can learn a lot more, and with a smaller investment in time, by simply "Googling" for information on what the cache is, and how it's used in modern *nix systems. For example, the following search term in Google yields numerous results that may help you: linux purpose of .cache. With that out of the way, I'd answer your questions as follows: What is ...


5

I always use the pinout website - its interactive and the best I have come across: https://pinout.xyz The image represents the circuit board and the edge between the mounting holes.


5

You SHOULD be able to power a USB HDD from the Pi3B+ as the USB ports can supply 1.2A. HOWEVER, I and others have found that this is often unreliable - this seems to be due to transient voltage drop when the disk starts. I have conducted a number of tests, and often the voltage on the USB ports is low. (I an using a rock solid external 5V power supply with ...


4

/boot/bcm2710-rpi-3-b-plus.dtb is missing in older Raspbian images. Just run sudo rpi-update on your booted previous Raspberry Pi to fetch the missing firmware. After that you can switch to your new Raspberry Pi 3B+ and boot it with your existing SD card.


4

Android Things hasn’t been updated for the Pi3B+ yet.


4

According to eLinux these cards with the respective part numbers (last column) should work fine. Samsung EVO microSDXC 128 10 MB-MP128GA/AM Samsung EVO PLUS microSDXC 128 10 MB-MC128DA/AMZ Samsung PRO+ microSDXC 128 10 UHS-I U3 MB-MD128DA/AM Besides these a few others, e.g. SanDisk are ...


4

Here is a solution with netbooting using sytemd-networkd. Network booting works only for the wired adapter. Booting over wireless LAN is not supported 1. It is also important that there is already a working DHCP server on the local network. We use RPi 3B+. It comes with "Improved PXE network and USB mass-storage booting" 2. So PXE booting will work out ...


4

There is no way to control any of the voltage rail pins (the 3V3 pins, the 5V pins, and the ground pins). They are hard wired to the input power line. The schematics are available at raspberrypi.org.


4

A Minecraft server uses port 25565 by default. The Minecraft server itself is a program that runs on a computer. The computer has an ip address, maybe 192.168.10.11, but there are running many programs, for example also a ssh server and a web server. If you want to connect to one of this server it is not enough to address it only with the ip address of the ...


4

Building scipy from source takes about 1hr20. Pre-compiled wheels are available from piwheels.org, so you can install it from there without building yourself. Raspbian Stretch is pre-configured to use piwheels. Are you on an older Raspbian version or another distribution? See piwheels.org for info on how to configure your system to use it or try: sudo pip3 ...


4

I assume you are using Raspbian and you have setup the access point with hostapd. To switch the access point this commands should do: rpi ~$ sudo systemctl stop hostapd.service rpi ~$ sudo systemctl start hostapd.service It is difficult to say much more about start/stop hostapd because I don't know anything about your setup. Do you use a stand alone access ...


4

The common way of doing this is having two sets of partitions. Initially, they are identical (modulo mount points in their corresponding grub and fstab configs). Call one the active set and the other the standby set. When new versions of anything are available, install them in whatever way you want on the standby set. If it gets corrupted because of a crash, ...


3

It's possible but it would be much easier just to get an adapter which are really cheap (probably £1 off eBay). The possible way to do this is to remove the card from the Raspberry PI, setup network booting (this is not trivial but there are lots of tutorials around including on raspberrypi.org) and then insert the card once the PI has booted. The PI ...


3

Raspberry Pi 3 model B+ is not yet officially supported by Android Things in contrast to Raspberry Pi 3 model B.


3

You need to use the new 'RetroPie 4.3.15 Stretch image'. This includes changes required for the Pi3B+ otherwise you will see issues that look like lack of power. https://retropie.org.uk/forum/topic/16307/retropie-4-3-15-stretch-images-for-testing


3

For the Pi3B+ you need to use the updated Raspbian image dated 2018-03-13. See https://www.raspberrypi.org/downloads/raspbian/ You can try the following which may work for you. It didn't work for me as I don't use the default repositories. sudo apt update sudo apt upgrade sudo apt dist-upgrade


3

Paragraph by paragraph So we’ve had a custom power supply from “Maxine” designed, so this is a four switch mode power supply, and so it’s “icy” controllable, and it sort of Hoover’s up a lot of the shrapnel on the board, like the discrete LDS that we had in the past. A new power supply from "Maxine" which is a four switch mode power supply that is I....


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