Tag Archive : Raspberry Pi

/ Raspberry Pi

Testing points on a Raspberry Pi

02/06/2018 | RADIO | 没有评论

Below is a list of test points which can be found on Raspberry Pi 2, 3 and some are also on b+.

With the use of a multimeter, these test points can help with troubleshooting hardware issues.

I have yet to find any formal documentation about these test points. However, I do know they exist.

PP3 GND
PP4 GND
PP5 GND
PP6 GND
PP7 5V after polyfuse
PP8 3V3
PP9 1V8
PP10 Goes from 3V3 to 2V on brownout
PP11 DAC_2V5 (for composite video DAC)
PP12 AUD_2V5 (for PWM audio drivers)
PP13 Goes from 3V3 to 2V on ACT activity
PP14 SD_CLK
PP15 SD_CMD
PP16 SD_DAT0
PP17 SD_DAT1
PP18 SD_DAT2
PP19 SD_DAT13
PP20 H5V
PP21 RUN signal (reset)
PP22 Goes from 3V3 to 2V on activity of green (link) ethernet jack LED
PP23 Goes from 3V3 to 2V on activity of yellow (speed) ethernet jack LED
PP24 COMPVID
PP25 AUDIO_L
PP26 AUDI_R
PP27 VBUS (USB 5V power)
PP28 ETH_CLK (25.000 MHz)
PP29 VC_TMS
PP30 VC_TRST_N
PP31 VC_CLK
PP32 VC_TDI
PP33 VC_TDO
PP34 GND
PP35 GPIO6 of LAN9514
PP36 GPIO7 of LAN9514
PP37 CAM_GPIO0
PP38 CAM_GPIO1
PP39 SCL0
PP40 SDA0

Below is an example of how you can use PP9 to confirm that the regulator is supplying 1.8v correctly.

Ground can be sourced from the SD card slot

And the exact location of PP9;

Adafruit has some great information covering the Raspberry Pi power circuitry. link

Expand your Pi-Star SD card

01/31/2018 | GUIDE | 没有评论

1. Expand the file system if you have not done so already

pi-star@pi-star(ro):~$ sudo pistar-expand
2. Reboot after the expand process completes.

pi-star@pi-star(ro):~$ sudo reboot

I have created a tool that uses various unicode block graphics characters to improve the resolution (compared to the canonical 2 pixel per characterapproach taken by other solutions posted here). It also automatically displays images in a thumbnail mode if multiple images are provided as input.

Installation:

git clone https://github.com/stefanhaustein/TerminalImageViewer.git
cd TerminalImageViewer/src/main/cpp
make
sudo make install

Usage:

tiv <image(s)>
More details at the github project: https://github.com/stefanhaustein/TerminalImageViewer

Example screenshot:

Raspberry Pi PIXEL UI install

01/30/2018 | GUIDE | 没有评论

The Raspbian + PIXEL image is available from the Downloads page on our website now. Note that the uncompressed image is over 4GB in size, and some older unzippers will fail to decompress it properly. If you have problems, use 7-Zip on Windows and The Unarchiver on Mac – both are free applications which have been tested to decompress the file correctly.

To update an existing Jessie image, type the following at the command line:

sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install -y rpi-chromium-mods
sudo apt-get install -y python-sense-emu python3-sense-emu
sudo apt-get install -y python-sense-emu-doc realvnc-vnc-viewer

and then reboot.

If you don’t use xrdp and would like to use the RealVNC server to remotely access your Pi, type the following:

sudo apt-get install -y realvnc-vnc-server

As always, your feedback on the new release is very welcome; feel free to let us know what you think in the comments or on the forums.

I’m following these directions, which are the same as these directions.

I have done update (twice) and upgrade. and I still get the “Unable to locate package” error:

$ sudo apt-get install realvnc-vnc-server realvnc-vnc-viewer
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package realvnc-vnc-server
E: Unable to locate package realvnc-vnc-viewer

The realvnc-vnc-server package isn’t in the repositories for jessie, but you can download the deb file VNC-Server-6.2.1-Linux-ARM.deb from here: https://www.realvnc.com/download/vnc/raspberrypi/

sudo wget https://www.realvnc.com/download/file/vnc.files/VNC-Server-6.2.1-Linux-ARM.deb

And install it manually with sudo dpkg –install filename

sudo dpkg -i VNC-Server-6.2.1-Linux-ARM.deb

install raspi-config

sudo apt-get install raspi-config

and then

How to rotate of RaspberryPi TFT display.

01/30/2018 | GUIDE | 没有评论

official info:https://www.raspberrypi.org/blog/the-eagerly-awaited-raspberry-pi-display/

如何反转180度:

sudo nano /boot/config.txt

在/boot/config.txt 中最后,回车新开启一行 加入:

lcd_rotate=2

Raspbian Sources Change

02/01/2017 | LINUX | 没有评论

下面有个列表,从树莓派实验室拿来的,大家随意取用:

中山大学
Raspbian http://mirror.sysu.edu.cn/raspbian/raspbian/
中国科学技术大学
Raspbian http://mirrors.ustc.edu.cn/raspbian/raspbian/
清华大学
Raspbian http://mirrors.tuna.tsinghua.edu.cn/raspbian/raspbian/
华中科技大学
Raspbian http://mirrors.hustunique.com/raspbian/raspbian/
Arch Linux ARM http://mirrors.hustunique.com/archlinuxarm/
大连东软信息学院源(北方用户)
Raspbian http://mirrors.neusoft.edu.cn/raspbian/raspbian/
重庆大学源(中西部用户)
Raspbian http://mirrors.cqu.edu.cn/Raspbian/raspbian/
新加坡国立大学
Raspbian http://mirror.nus.edu.sg/raspbian/raspbian
牛津大学
Raspbian http://mirror.ox.ac.uk/sites/archive.raspbian.org/archive/raspbian/
韩国KAIST大学
Raspbian http://ftp.kaist.ac.kr/raspbian/raspbian/
更新自己的/etc/apt/sources.list里面的内容即可,就是要注意自己的源的版本,别把jessie更新成了wheezy,也别弄反了。我的系统是Jessie的,所以,你懂得。

编辑/etc/apt/sources.list 文件,参考如下命令:

sudo cp /etc/apt/sources.list{,.bak}
cat > /etc/apt/sources.list << EOF
deb http://mirror.sysu.edu.cn/raspbian/raspbian/ Jessie main contrib non-free
deb-src http://mirror.sysu.edu.cn/raspbian/raspbian/ Jessie main contrib non-free
EOF

注:网址末尾的raspbian重复两次是必须的。因为Raspbian的仓库中除了APT软件源还包含其他代码。APT软件源不在仓库的根目录,而在raspbian/子目录下。

编辑镜像站后,请使用sudo apt-get update命令,更新软件源列表,同时检查您的编辑是否正确。
如果需要, 你可以执行以下命令将Raspbian public key加入你的 apt-get keyring :

wget http://archive.raspbian.org/raspbian.public.key -O - | sudo apt-key add -