Engineering and technology

Gherman Titov

Jovan Stosic September 13, 2020

Gherman Stepanovich Titov (Russian: Герман Степанович Титов; 11 September 1935 – 20 September 2000) was a Soviet cosmonaut who, on 6 August 1961, became the second human to orbit the Earth, aboard Vostok 2, preceded by Yuri Gagarin on Vostok 1. He was the fourth person in space, counting suborbital voyages of US astronauts Alan Shepard and Gus Grissom.

Titov’s flight finally proved that humans could live and work in space. He was the first person to orbit the Earth multiple times (a total of 17), the first to pilot a spaceship and to spend more than a day in space. He was also the first to sleep in orbit and to suffer from space sickness (becoming the first person to vomit in space).

Titov made the first manual photographs from orbit, thus setting a record for modern space photography. He also was the first person to film the Earth using a professional quality Konvas-Avtomat movie camera, which he used for ten minutes. A month short of 26 years old at launch, he remains the youngest person to fly in space.

In his subsequent life Titov continued to work for the Soviet space program, and played a major role in the Spiral project where he trained to become the first pilot of an orbital spaceplane. However, after the death of Yuri Gagarin in a military aircraft accident in 1968, the Soviet government decided it could not afford to lose its second cosmonaut, and so Titov’s career as test pilot ended.

Titov served in the Soviet Air Force, attaining the rank of colonel-general. In his final years in post-Soviet Russia he became a Communist politician. Despite having been chosen second, after Gagarin, to fly into space, it was Titov who later proposed the Soviet Government regularly celebrate Cosmonautics Day on April 12, the day of Gagarin’s flight.

https://en.wikipedia.org/wiki/Gherman_Titov

Vladimir Komarov

Jovan Stosic September 13, 2020

Vladimir Mikhaylovich Komarov (Russian: Влади́мир Миха́йлович Комаро́в, IPA: [vlɐˈdʲimʲɪr mʲɪˈxaɪləvʲɪtɕ kəmɐˈrof]; 16 March 1927 – 24 April 1967) was a Soviet test pilot, aerospace engineer, and cosmonaut. In October 1964, he commanded Voskhod 1, the first spaceflight to carry more than one crew member. He became the first Soviet cosmonaut to fly in space twice when he was selected as the solo pilot of Soyuz 1, its first crewed test flight. A parachute failure caused his Soyuz capsule to crash into the ground after re-entry on 24 April 1967, making him the first human to die in a space flight.

Komarov was one of the most highly experienced and qualified candidates accepted into the first squad of cosmonauts selected in 1960. He was declared medically unfit for training or spaceflight twice while he was in the program, but his perseverance, superior skills, and engineering knowledge allowed him to continue playing an active role. During his time at the cosmonaut training center, he contributed to space vehicle design, cosmonaut training, evaluation and public relations.

https://en.wikipedia.org/wiki/Vladimir_Komarov

ESP8266 Pinout Reference: Which GPIO pins should you use?

Jovan Stosic August 26, 2020
Label GPIO Input Output Notes
D0 GPIO16 no interrupt no PWM or I2C support HIGH at boot
used to wake up from deep sleep
D1 GPIO5 OK OK often used as SCL (I2C)
D2 GPIO4 OK OK often used as SDA (I2C)
D3 GPIO0 pulled up OK connected to FLASH button, boot fails if pulled LOW
D4 GPIO2 pulled up OK HIGH at boot
connected to on-board LED, boot fails if pulled LOW
D5 GPIO14 OK OK SPI (SCLK)
D6 GPIO12 OK OK SPI (MISO)
D7 GPIO13 OK OK SPI (MOSI)
D8 GPIO15 pulled to GND OK SPI (CS)
Boot fails if pulled HIGH
RX GPIO3 OK RX pin HIGH at boot
TX GPIO1 TX pin OK HIGH at boot
debug output at boot, boot fails if pulled LOW
A0 ADC0 Analog Input X

Source: ESP8266 Pinout Reference: Which GPIO pins should you use? | Random Nerd Tutorials

18.04 – Blueman Protocol not available

Jovan Stosic August 23, 2020

Today my bluetooth headset stopped working. I haven’t modified anything recently (although a few days ago I was trying to get a bluetooth headset to automatically connect in a2dp mode, which involved installing blueman and re-pairing with it, but I’ve connected and rebooted several times since making that change and everything was working).

Now when I try to connect the headset I get:

Connection Failed: blueman.bluez.errors.DBusFailedError: Protocol Not available

Based on a few things from here (Bluetooth – Connection Failed: blueman.bluez.errors.DBusFailedError: Protocol Not available) and other Internet searches, I’ve tried:

$ sudo apt-get install pulseaudio-module-bluetooth
$ pactl load-module module-bluetooth-discover

And I’ve tried reinstalling things:

$ sudo apt-get --purge --reinstall install bluetooth bluez blueman pulseaudio pulseaudio-module-bluetooth
$ sudo /etc/init.d/networking restart
    [ ok ] Restarting networking (via systemctl): networking.service.
$ sudo /etc/init.d/bluetooth restart
    [ ok ] Restarting bluetooth (via systemctl): bluetooth.service.

And of course rebooting, but nothing seems to help, and I can’t figure out what protocol it’s talking about, since I can see the headset and pair with it, but not make an audio connection.

I’m running Ubuntu 18.04.1. Some other details:

$ dpkg -l | grep blue
    blueman                            2.0.5-1ubuntu1    
    bluetooth                          5.48-0ubuntu3.1
    bluez                              5.48-0ubuntu3.1
    bluez-cups                         5.48-0ubuntu3.1
    bluez-obexd                        5.48-0ubuntu3.1
    gir1.2-gnomebluetooth-1.0:amd64    3.28.0-2ubuntu0.1
    gnome-bluetooth                    3.28.0-2ubuntu0.1
    indicator-bluetooth                0.0.6+17.10.20170605-0ubuntu3                
    libbluetooth3:amd64                5.48-0ubuntu3.1                              
    libgnome-bluetooth13:amd64         3.28.0-2ubuntu0.1
    pulseaudio-module-bluetooth        1:11.1-1ubuntu7.1

$ sudo service bluetooth status
* bluetooth.service - Bluetooth service    Loaded: loaded (/lib/systemd/system/bluetooth.service; enabled; vendor preset    Active: active (running) since Mon 2019-02-04 14:36:47 PST; 1min 13s ago
     Docs: man:bluetoothd(8)  Main PID: 6912 (bluetoothd)    Status: "Running"
    Tasks: 1 (limit: 4915)    CGroup: /system.slice/bluetooth.service
           └─6912 /usr/lib/bluetooth/bluetoothd

Feb 04 14:36:47 AVB systemd[1]: Starting Bluetooth service... Feb 04 14:36:47 AVB bluetoothd[6912]: Bluetooth daemon 5.48 Feb 04 14:36:47 AVB systemd[1]: Started Bluetooth service. Feb 04 14:36:47 AVB bluetoothd[6912]: Starting SDP server Feb 04 14:36:47 AVB bluetoothd[6912]: Bluetooth management interface 1.14 initialized

$ dmesg | grep Bluetooth
    [    5.197632] Bluetooth: Core ver 2.22
    [    5.197654] Bluetooth: HCI device and connection manager initialized
    [    5.197657] Bluetooth: HCI socket layer initialized
    [    5.197660] Bluetooth: L2CAP socket layer initialized
    [    5.197664] Bluetooth: SCO socket layer initialized
    [    5.349217] Bluetooth: hci0: Firmware revision 0.1 build 185 week 49 2017
    [    5.492623] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
    [    5.492625] Bluetooth: BNEP filters: protocol multicast
    [    5.492628] Bluetooth: BNEP socket layer initialized
    [   16.972106] Bluetooth: RFCOMM TTY layer initialized
    [   16.972113] Bluetooth: RFCOMM socket layer initialized
    [   16.972117] Bluetooth: RFCOMM ver 1.11
    [   84.672241] Bluetooth: hci0: last event is not cmd complete (0x0f)

$ hciconfig
    hci0:    Type: Primary  Bus: USB
    BD Address: 74:70:FD:B6:73:0C  ACL MTU: 1021:4  SCO MTU: 96:6
    UP RUNNING PSCAN ISCAN INQUIRY
    RX bytes:18753 acl:61 sco:0 events:738 errors:0
    TX bytes:14257 acl:60 sco:0 commands:267 errors:0

$ lspci -knn | grep Net -A3
    02:00.0 Network controller [0280]: Intel Corporation Wireless 8265 / 8275 [8086:24fd] (rev 78)
    Subsystem: Intel Corporation Dual Band Wireless-AC 8265 [8086:0010]
    Kernel driver in use: iwlwifi
    Kernel modules: iwlwifi

$ lsusb
    Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
    Bus 001 Device 003: ID 8087:0a2b Intel Corp.
    Bus 001 Device 002: ID 13d3:5a07 IMC Networks
    Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

$ ps aux | grep blue
    me        2032  0.0  0.6 694048 54240 tty2     Sl+  14:19   0:01 /usr/bin/python3 /usr/bin/blueman-applet
    me        2091  0.0  0.0  82728  6832 ?        Ss   14:19   0:00 /usr/lib/bluetooth/obexd
    root      6912  0.0  0.0  37992  6096 ?        Ss   14:36   0:02 /usr/lib/bluetooth/bluetoothd

Any suggestions on where to look next? Thanks.

 
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  • 3
    I might have solved this myself. “sudo apt install pulseaudio-module-bluetooth” and then restarting pulse audio (“pulseaudio -k” “pulseaudio –start”) and the error goes away. I still have no idea why this is necessary or what the error originally meant. – M. P. Feb 5 ’19 at 17:53

2 Answers

ActiveOldestVotes

20

For me just reloading the module by executing:

pactl unload-module module-bluetooth-discover
pactl load-module module-bluetooth-discover

helped solving the issue.

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  • 4
    Works with 19.04 too. The module must be unloaded first pactl unload-module module-bluetooth-discover. – Vladimir Botka Oct 4 ’19 at 14:59
  • This is the only thing that worked for me with my Bose 700 headphones using blueman on cinnamon. Didn’t even have to restart bluetooth service and didn’t have to run the commands above as root. – Plasty Grove Jul 28 at 2:56

1

Just delete the device on bluetooth manager and pair again. Works for me.

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Source: 18.04 – Blueman Protocol not available – Ask Ubuntu

HardwareSupportComponentsBluetoothUsbAdapters – Ubuntu Wiki

Jovan Stosic August 23, 2020

Introduction

This page lists some of the Bluetooth USB Adapters that work on Ubuntu. For help with Bluetooth in Ubuntu, see the community documentation on Setting up Bluetooth. You may also want to consider purchasing a free software compatible device. Unlike non-free driver dependent hardware support exists out of the box and will continue working going forward. Many other Bluetooth dongles will not. Free software compatible adapters are available from stores such as ThinkPenguin.com.

To get information about you BlueTooth device use commands:

$ lsusb
...
Bus 002 Device 005: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
...
$ hciconfig
hci0:   Type: USB
...
$ hciconfig -a hci0
...
        Manufacturer: Accel Semiconductor Ltd. (74)

Source: HardwareSupportComponentsBluetoothUsbAdapters – Ubuntu Wiki