Thursday, November 28, 2019

Mauritius underwater waterfall from airplane

When I went to Mauritius, I could see it from Airplane.

Sunday, October 13, 2019

Raspberry pi zero and USB3 memory stick

Raspberry pi Zero (Pi-Zero) may not be able to recognize USB3 devices because of a power shortage of USB port. My Extreme Pro USB3.0 stick (128G, SANDISK) is not recognized by Pi-Zero without using a self-powered USB hub. However, a self-powered USB hub is too inconvenience to carry due to a bulky AC adapter.

The "max_usb_current=1" in the /boot/config.txt, which changes the Maximum USB current to 1.2 A, is not effective for Pi-Zero

I am using "Double-Powered USB hub (USB-HUB227WH3, SANWA supply, JAPAN)" which I bought very long ago.


If the Red connector is connected to a USB port or a power adapter, electrical power of USB hub is overloaded above 1A, like a self-powered Hub.  It can also be used as a bus-powered hub without using the Red connector.

With the USB-OTG setting, My USB3.0 memory stick can be used in Pi-Zero by connecting the red connecter to a 1A power adapter only.

Needless to say, just USB2.0 speed.

Wednesday, May 15, 2019

HDMI to VGA Converter may become alternative of HDMI Display Emulator for headless PC

Most of stick PC including my Meegopad T-01 cannot be used without monitor (headless PC).  HDMI dummy plug (Display Emulator) must be necessary.

However,  HDMI to VGA Converter which is no use at present may become alternative of Display Emulator. I can access the monitor-less Meegopad T-01 by remote desktop with VGA converter.

Saturday, April 27, 2019

Remote desktop on Ubuntu-Mate for Raspberry pi

The long-awaited Ubuntu-Mate 18.04 for Raspberry pi is disclosed !!

I immediately installed for my Raspberry pi3.

However, the remote desktop from windows (xRDP) does not work well but only shows black screen.

From web information, several configurations are required for xRDP on ubuntu-mate 18.04.

My setting for xRDP and more is below.

1.
sudo apt-get update
sudo apt-get upgrade

2. (not for xRDP)
sudo apt-get install hardinfo ntp cifs-utils

3.
sudo apt-get install tightvncserver xrdp

4. EDIT "/etc/xrdp/startwm.sh"
Insert below two lines 
             unset DBUS_SESSION_BUS_ADDRESS
             exec mate-session
before the line "test -x /etc/X11/Xsession && exec /etc/X11/Xsession"

5. EDIT "/etc/X11/Xwrapper.config"
Add below to the last line
           allowed_users=anybody
           needs_root_rights=no

6. EDIT "/boot/config.txt" (not for xRDP)
Add below to the last line
           # turn power LED into heartbeat
           dtparam=pwr_led_trigger=heartbeat

7.
sudo reboot