NuttX RTOS is now Apache TLP

My favorite NuttX RTOS [1] that is “Tiny Unix on MCU” has graduated to Apache Top-Level-Project [2], congratulations! :-)

Apache NuttX [1] is a real-time operating system (RTOS) that emphasizes standards compliance and small footprint, usable in all but the tightest micro-controller environments. It runs on 8-bit, 16-bit, 32-bit, and 64-bit microcontrollers across RISC-V, ARM, MIPS, ESP32, AVR, x86, and other architectures with a high degree of standards compliance. NuttX is used to power the Fitbit fitness tracker, as well as satellites, IoT devices, bluetooth headphones, drones, and more.

What I like most in NuttX is the development team / community.. and scalability starting upwards from 8-bit CPU’s. One day I wish porting NuttX to my 8-bit Atari and 16-bit Amiga and Atari ST and push new life to these amazing machines :-)

[1] https://nuttx.apache.org
[2] https://news.apache.org/foundation/entry/the-apache-software-foundation-announces-apache-nuttx-as-a-top-level-project

M2.NVM disk + PCI-E controller on FreeBSD

Modern laptops are quite expensive and hard to upgrade. While they are really handy to work in multiple places, they are not that efficient for advanced R&D activities like virtualization and massive software development combined (I/O speeds highly affects overall performance and compilation times). I was wondering if M2.NVM disk over PCI-E controller could work with my old desktop workstation giving additional performance benefit over standard onboard SATA attached SSD drive.

Old desktop PC only supports SATA drives. Switching to SATA SSD (electronics NAND Flash based Solid State Drive) in place of conventional HDD (mechanical drive) can boost I/O performance noticeably. We had 3.5″ (desktop) and 2.5″ (laptop) physical disk dimensions available so far. But new M2 SSD drives showed up, founding a new standard, with smaller form factor to be installed in embedded systems and lightweight laptops. M2 defines only a physical dimensions requirements, while disk itself can implement SATA (with average 500MB/s read/write speed) or NVM (with average 3000MB/s read/write speeds or better) interface.

So I have decided to try M2.NVM Samsung SSD 980 1TB drive over ICYBOX IB-PCI224M2-ARGB PCI-E 4.0 controller on my ASUS M5A97 R2.0 (last available BIOS 2603) that only supports PCI-E 2.0. I have several internal and external SSD SATA drives both in 2.5″ and M2 form factor. Having even basic M2.NVM drive over PCI-E controller seems to be more future proof purchase, for the same amount of money, it will be ready for possible motherboard replacement, and in bay benefit in additional performance gain over onboard SATA attached SSD drive. Operating system is Open-Source FreeBSD Unix version 13-STABLE, filesystem is ZFS (testing done with no compression and no encryption).

It turns out that PCI-E 4.0 card can work on older PCI-E 2.0 bus (for sure speed will be degraded in that case). Mainboard BIOS does not see the NVM controlleri in UEFI mode (TODO) so it is not possible to boot out of it without additional SATA drive with the FreeBSD bootloader / kernel first (TODO). FreeBSD can see and utilize both PCI-E Controller and the M2.NVM drive with no problem. Let’s see the data transfer speed results in numbers.

Average in-filesystem StressDisk large file write speed results:

  • Onboard SATA 2x WDEARS RED 2TB ZFS RAID0 STRIPE: 188MB/s.
  • PCI-E ICYBOX M2.NVM Samsung SSD 980 1TB ZFS: 410MB/s.

DiskInfo single drive summary results:

  • PCI-E ICYBOX M2.NVM Samsung SSD 980 1TB ZFS: O:1087557, M:1099090, I:1160432 kbytes/sec
  • Onboard SATA 3.5″ 2TB 5400RPM HDD WD20EFRX (RED):O:146521, M:116847, I:70159 kbytes/sec
  • Onboard SATA 3.5″ 2TB 5400RPM HDD WDEARS (GREEN): O:113811, M:87543, I:49209 kbytes/sec
  • External USB3.1 M2.SATA SSD disk enclosure: O:31503, M:31850, I:31900 kbytes/sec.

As we can see above, from user perspective in out-of-the-box configuration write speeds are 218% faster on NVM SDD over HDD RAID for large files (this may need some filesystem tuning). Weighted average disk access for NVM SSD is 1 115 693 KB/s, WD20EFRX is 111 176 KB/s, WDEARS is 83 521 KB/s. It turns out that WD RED HDD disks are 133% faster than WD GREEN HDD disks, while NVM SSD disks are over 1000% faster than WD HDD RED disks. On the other hand external USB 3.1 M2.SATA SSD disk has average 47 626 KB/s results. One last but crucial test will be added here containing the onboard SATA SSD drive, just to make sure and prove NVM dominance over SATA.

DiskInfo result for single 3.5″ 2TB 5400RPM HDD WDEARS (GREEN Series) drive attached to onboard SATA controller:

# diskinfo -tv /dev/ada2
/dev/ada2
        512             # sectorsize
        2000398934016   # mediasize in bytes (1.8T)
        3907029168      # mediasize in sectors
        4096            # stripesize
        0               # stripeoffset
        3876021         # Cylinders according to firmware.
        16              # Heads according to firmware.
        63              # Sectors according to firmware.
        WDC WD20EARS-00MVWB0    # Disk descr.
        XXX             # Disk ident.
        ahcich4         # Attachment
        No              # TRIM/UNMAP support
        Unknown         # Rotation rate in RPM
        Not_Zoned       # Zone Mode

Seek times:
        Full stroke:      250 iter in   7.135585 sec =   28.542 msec
        Half stroke:      250 iter in   5.288793 sec =   21.155 msec
        Quarter stroke:   500 iter in   7.540787 sec =   15.082 msec
        Short forward:    400 iter in   3.036829 sec =    7.592 msec
        Short backward:   400 iter in   2.956946 sec =    7.392 msec
        Seq outer:       2048 iter in   0.254515 sec =    0.124 msec
        Seq inner:       2048 iter in   0.199511 sec =    0.097 msec

Transfer rates:
        outside:       102400 kbytes in   0.899735 sec =   113811 kbytes/sec
        middle:        102400 kbytes in   1.169709 sec =    87543 kbytes/sec
        inside:        102400 kbytes in   2.080911 sec =    49209 kbytes/sec

DiskInfo result for single 3.5″ 2TB 5400RPM HDD WD20EFRX (RED Series) drive attached to onboard SATA controller:

# diskinfo -tv /dev/ada0
/dev/ada0
        512             # sectorsize
        2000398934016   # mediasize in bytes (1.8T)
        3907029168      # mediasize in sectors
        4096            # stripesize
        0               # stripeoffset
        3876021         # Cylinders according to firmware.
        16              # Heads according to firmware.
        63              # Sectors according to firmware.
        WDC WD20EFRX-68EUZN0    # Disk descr.
        XXX             # Disk ident.
        ahcich0         # Attachment
        No              # TRIM/UNMAP support
        5400            # Rotation rate in RPM
        Not_Zoned       # Zone Mode

Seek times:
        Full stroke:      250 iter in   6.653120 sec =   26.612 msec
        Half stroke:      250 iter in   5.172312 sec =   20.689 msec
        Quarter stroke:   500 iter in   7.808667 sec =   15.617 msec
        Short forward:    400 iter in   2.082164 sec =    5.205 msec
        Short backward:   400 iter in   3.350534 sec =    8.376 msec
        Seq outer:       2048 iter in   0.141464 sec =    0.069 msec
        Seq inner:       2048 iter in   0.139262 sec =    0.068 msec

Transfer rates:
        outside:       102400 kbytes in   0.698874 sec =   146521 kbytes/sec
        middle:        102400 kbytes in   0.876360 sec =   116847 kbytes/sec
        inside:        102400 kbytes in   1.459537 sec =    70159 kbytes/sec

DiskInfo result for single M2.NVM Samsung SSD 980 1TB drive attached to ICYBOX IB-PCI224M2-ARGB PCI-E 4.0 controller working on PCI-E 2.0 capable motherboard:

# diskinfo -tv /dev/nvd0
/dev/nvd0
        512             # sectorsize
        1000204886016   # mediasize in bytes (932G)
        1953525168      # mediasize in sectors
        4096            # stripesize
        0               # stripeoffset
        Samsung SSD 980 1TB     # Disk descr.
        XXX             # Disk ident.
        nvme0           # Attachment
        Yes             # TRIM/UNMAP support
        0               # Rotation rate in RPM

Seek times:
        Full stroke:      250 iter in   0.008369 sec =    0.033 msec
        Half stroke:      250 iter in   0.005510 sec =    0.022 msec
        Quarter stroke:   500 iter in   0.014519 sec =    0.029 msec
        Short forward:    400 iter in   0.010368 sec =    0.026 msec
        Short backward:   400 iter in   0.020456 sec =    0.051 msec
        Seq outer:       2048 iter in   0.032788 sec =    0.016 msec
        Seq inner:       2048 iter in   0.032863 sec =    0.016 msec

Transfer rates:
        outside:       102400 kbytes in   0.094156 sec =  1087557 kbytes/sec
        middle:        102400 kbytes in   0.093168 sec =  1099090 kbytes/sec
        inside:        102400 kbytes in   0.088243 sec =  1160432 kbytes/sec

DiskInfo resuls for USB 3.1 M2.SATA SSD disk enclosure:

 # diskinfo -tv /dev/da0
/dev/da0
        512             # sectorsize
        256060514304    # mediasize in bytes (238G)
        500118192       # mediasize in sectors
        4096            # stripesize
        0               # stripeoffset
        31130           # Cylinders according to firmware.
        255             # Heads according to firmware.
        63              # Sectors according to firmware.
        USB3.1          # Disk descr.
        XXX             # Disk ident.
        umass-sim0      # Attachment
        No              # TRIM/UNMAP support
        Unknown         # Rotation rate in RPM
        Not_Zoned       # Zone Mode

Seek times:
        Full stroke:      250 iter in   0.096377 sec =    0.386 msec
        Half stroke:      250 iter in   0.099408 sec =    0.398 msec
        Quarter stroke:   500 iter in   0.216023 sec =    0.432 msec
        Short forward:    400 iter in   0.190744 sec =    0.477 msec
        Short backward:   400 iter in   0.203053 sec =    0.508 msec
        Seq outer:       2048 iter in   0.769551 sec =    0.376 msec
        Seq inner:       2048 iter in   0.769675 sec =    0.376 msec

Transfer rates:
        outside:       102400 kbytes in   3.250481 sec =    31503 kbytes/sec
        middle:        102400 kbytes in   3.215029 sec =    31850 kbytes/sec
        inside:        102400 kbytes in   3.210055 sec =    31900 kbytes/sec

FreeBSD single user remount / rw

If you are using UFS you can remount the root while in single mode with

mount -u w /

If you are using ZFS you can remount the root while in single mode with

zfs set readonly=off zroot

Note: With ZFS there is no need to turn back readonly=on as this will keep read-only flag while in userland mode :-)

BSD Chromium Audio/Mic

If you encounter a problem with microphone in Chromium on FreeBSD (and other *BSD), this is because it uses sndio audio backend and probably default microphone is not the one you want to use. In my case /dev/dsp0 is the HDMI input/output thus no audio input. There is no need to start system wide sndiod. You can use environment variables in ~/.profile to control audio input/output for the local spawning sndio client:

  • export AUDIODEVICE="rsnd/4" sets default input/output device to /dev/dsp4.
  • export AUDIORECDEVICE="rsnd/3" sets default input device to /dev/dsp3.
  • export AUDIOPLAYDEVICE="rsnd/2" sets default output device to /dev/dsp2.

You can simply set AUDIODEVICE="rsnd/4" to switch default input and output device, and/or AUDIORECDEVICE="rsnd/3" to change default microphone source. If you want to have choice to switch between several devices on the fly you will need to use sndiod and provide set of devices with -f flag. See sndio [1] and sndiod [2] man pages for more information.
[1] https://man.openbsd.org/sndio.
[2] https://man.openbsd.org/sndiod

FreeBSD + Zephyr RTOS + ESP32

FreeBSD can natively emulate Linux ELF binaries. You can now bootstrap Linux espressif xtensa toolchain for ESP32 on FreeBSD under The Zephyr Project with west espressif install :-)
https://github.com/espressif/esp-idf/pull/7226#event-5064755416

CED 7000 battery replacement

If you need to replace battery for CED 7000 timer [1] you can either buy a HLP 443450 3.7V 800mAh 2.96Wh accumulator [2] or dedicated inexpensive Power Bank [3] that contains two accumulators inside – one for quick replacement of the timer battery and the other to charge timer over the USB cable – this way you can also safely carry a backup and replacement power source at hand :-) One thing that could be improved here is using both accumulators in the Power Bank so capacity is doubled and both are always charged – that should also prevent self-discharge below safe point of the unused unit.





[1] https://www.cedhk.com/ced7000-shot-timer
[2] https://www.cedhk.com/ced7000-replacement-battery
[3] https://www.halinka-arms.pl/timery-i-akcesoria/1096-power-bank-do-timera-ced-7000.html

ZEPHYR RTOS ROX!

If you never heard about Free-and-Open-Source ZEPHYR RTOS [1] (Apache 2.0 licensed) then it will make your day as the best platform out there for your new embedded electronics design :-) It works on anything.. even on Open-Source-Hardware RISC-V CPU [2] :-)

[1] https://zephyrproject.org/
[2] https://riscv.org/

Make PDF small with GS

With this trick you can make your PDF smaller even 10x with no noticable picture quality loss :-)

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dBATCH  -dQUIET -dDownsampleColorImages=true -dColorImageResolution=200 -dColorImageDownsampleType=/Bicubic -sOutputFile=output.pdf input.pdf

Xilinx USB JTAG Platform Cable Vivado Linux

If you work with Xilnx Vivado Design Suite [1] for FPGA development using USB JTAG interface such as Xilinx USB Platform Cable [2] or its cheaper clone from WaveShare [3], everything seems to be connected properly, but it cannot find the Target for programming, you probably need to perform drivers setup manually [4]. Error message looks like this:

ERROR: [Labtoolstcl 44-494] There is no active target available for server at localhost.
Targets(s) ", jsn3" may be locked by another hw_server.

Error message may indicate that another instance of hw_server is running in the background but that is not the case. Check your drivers first [4]. Some hints:

  • Run as root and be careful as this will modify your OS.
  • Install script location is Vivado/2020.2/data/xicom/cable_drivers/lin64/install_script/install_drivers.
  • Platform Cable USB interface is pcusb.
  • Make sure UDEV rules are installed in /etc/udev/rules.d/ (i.e. 52-xilinx-pcusb.rules file).
  • After drivers are set up remember to restart UDEV with service udev restart command and re-attach your USB JTAG cable.

[1] https://www.xilinx.com/products/design-tools/vivado.html
[2] https://www.xilinx.com/products/boards-and-kits/hw-usb-ii-g.html
[3] https://www.waveshare.com/platform-cable-usb.htm
[4] https://www.xilinx.com/support/answers/54381.html

DSO QUAD MINI SCOPE ACCU REPLACEMENT

If you are happy user of DSO QUAD pocket oscilloscope from Seeed Studio [1] then probably after all those years you need to replace the accumulator. Because stock model PL384070 3.7V 1000mAh is not available anymore you can safely use CL404070 3.7V 1300mAh that is only 0.2mm thicker but it also fits the scope very well and you gain 30% capacity. You only have to solder the plug from the old accumulator. Enjoy :-)







[1] https://www.seeedstudio.com/DSO-Quad-Aluminium-Alloy-Black-p-1034.html

Why Linux Sux?

Imagine you have a disk full of your precious data that you want to mount to a new Ubuntu Linux system and add user to match the existing home directory.

# adduser user
Adding user `user' ...
Adding new group `user' (1000) ...
Adding new user `user' (1000) with group `user' ...
Creating home directory `/home/user' ...
Stopped: Couldn't create home directory `/home/user': File exists.

Removing directory `/home/user' ...
Removing user `user' ...
Removing group `user' ...
groupdel: group 'user' does not exist
adduser: `groupdel user' returned error code 6. Exiting.

Now you can say your all precious data goodbye. No questions asked. Core Linux utility adduser just found your existing data and erased them without even asking. The years is 2021 (30 years since Linux was created).

This is why for over 15 years I am only working with BSD Operating Systems [1] [2] [3] [4]. Its Open-Source with long-term maintenance and self-compatibility in mind.  BSD license is even more liberal than GPL for your products [5]. You should try BSD too :-)

[1] https://www.freebsd.org/
[2] https://www.openbsd.org/
[3] https://netbsd.org/
[4] https://www.dragonflybsd.org/
[5] https://en.wikipedia.org/wiki/List_of_products_based_on_FreeBSD

Synaptics TouchPad on Panasonic CF-MX4

This wulf7 [1] is a really nice guy that helped me run full featured Synaptics TouchPad with FreeBSD on Panasonic Toughbook CF-MX4 [2][3]. Now it works for moused and libinput with all multitouch gestures like two or three finger scroll, scale, etc! The problem was in detection mechanism as device is connected over multiplexer with both PS/2 and SMBus but multitouch works only over SMBus. Although fix requires change and rebuild of FreeBSD Kernel I hope it gets quickly to the upstream [4]. I had a chance to exercise building whole FreeBSD distribution into the USB memstick image, so I could test driver fix on a target computer without even touching its hard drive contents :-)

/* psm has a special support for GenMouse + SynTouchpad combination */
if (active_ports_count >= 2) {
    for (port = 0; port < KBDC_AUX_MUX_NUM_PORTS; port++) {

That 2 above had to be changed into 1 in /usr/src/sys/dev/atkbdc/psm.c. Nice? That’s what I call a one-bit-fix :-)

In addition, when you work with Synaptics Touchpad in Xorg and you want to use its all features like tap-to-click, natural (swapped) two finger scroll, two and three finger gestures, don’t use moused,xmodmap, or xinput as this will produce inconsistent behavior in applications based on different toolkits (i.e. GTK will scroll up while Qt will scroll down etc), instead use the new way of input based on libinput and modify MatchIsTouchpad section of /usr/local/share/X11/xorg.conf.d/40-libinput.conf like:

Section "InputClass"
        Identifier "libinput touchpad catchall"
        MatchIsTouchpad "on"
        MatchDevicePath "/dev/input/event5"
        Option "NaturalScrolling" "on"
        Option "Tapping" "on"
        Option "ClickMethod" "clickfinger"
        Driver "libinput"
EndSection

[1] https://github.com/wulf7/iichid
[2] https://github.com/wulf7/iichid/issues/51
[3] https://github.com/wulf7/iichid/issues/53
[4] https://reviews.freebsd.org/D28502

Website Look Update 2021

I have updated the website look. I hope you like it :-)

Disable Comments in WordPress

You can disable comments for existing posts using Bulk Edit, but this is not possible for existing media files. You can do both with a single SQL command :

UPDATE wp_your_table_with_posts SET comment_status = 'closed';

You can disable comments for all new posts either by hand as administrator unchecking Settings / Discussion / Allow people to submit comments on new posts, or using SQL command:

UPDATE wp_your_table_with_options SET option_value = NULL WHERE option_name = 'default_comment_status';

LimeSuite on FreeBSD

I have ported LimeSuite [1] to FreeBSD [2]. You can now work with LimeSDR [3] / LimeSDR-Mini [4] and others on my favourite OS. Please visit MyriadRF [5] for various radio inspirations. Have fun! :-)

[1] https://github.com/myriadrf/LimeSuite
[2] https://www.freebsd.org/
[3] https://limemicro.com/products/boards/limesdr/
[4] https://limemicro.com/products/boards/limesdr-mini/
[5] https://myriadrf.org/

Panasonic Toughbook WWAN modem unlock

If you have Panasonic Toughbook laptop with no LTE/4G cellular modem and after you attach internal modem but it is still not visible in BIOS Setup nor in the Operating System, go to the Main / Optional Kit Configuration, use toughkit password, then set Wireless WAN ID = 15 (in case you use original Sierra Wireless EC7305 device). WWAN card should be now available both in BIOS Setup and Operating System USB port. Enjoy! :-)

Damn slow Windows 10 boot

If you encounter turtle slow Windows 10 boot time on a decent machine it may be caused by AMD/Radeon driver’s ULPS. Try the following:
1. Launch REGEDIT.
2. Search for “enableulps” key.
3. Set its value from 1 to 0.
4. Reboot and see if that helped :-)

Mounting external ZFS volume

If you need to perform a data recovery from an external ZFS [zfs] volume you may find those hinds helpful:

  1. Attach encrypted partition where ZFS pool resides with:
    geli attach /dev/your_device_partition
  2. Import ZFS pool at given mountpoint (/mnt/zfs):
    zpool import -af -R /mnt/zfs
  3. Modify mount point location for a given dataset that may have mountpoint set to none what marks it as no mount (note this mountpoint will append to parent mount point location):
    zfs set mountpoint=ROOT zroot/ROOT/default
  4. Mount and mount all pool datasets:
    zfs mount -a
    zfs umount -a
  5. Mount/umount given dataset:
    zfs mount zroot/ROOT/default
  6. You can verify if your ZFS pool is active with:
    zpool status
  7. You can see what ZFS datasets are available with mount points with:
    zfs list

[zfs] https://www.freebsd.org/doc/handbook/zfs.html

ZFS on SSD CAM/CRC errors

If you encounter lots of CAM/CRC errors when using encrypted ZFS on some SSD drives on FreeBSD, that is caused by TRIM. You need to disable it in boot loader prompt or add below line to /boot/loader.conf:

vfs.zfs.trim.enabled=0

netsh winsock reset

If you encounter any strange network related behavior on a windows based pc, especially after windows update, use this to resolve most of the problems and save some time, remember to reboot pc afterwards ;-)

netsh winsock reset

macOS Virtual Audio SoundFlower Loopback

SoundFlower [1] is amazing Free and Open-Source extension to macOS BSD that allows you to create Virtual Audio Device in order to Route and Record Applications Audio. This is especially important for activities like Online Streaming and Presentation/Lectures Recording.

If you need more advanced Audio Routing with a nice GUI and lots of options try Loopback [2] from RogueAmoeba [3].

Thank you for this amazing fork and keeping it Open-Source! :-)

[1] https://github.com/mattingalls/Soundflower
[2] https://rogueamoeba.com
[3] https://rogueamoeba.com/loopback

GRUB Remember Last Boot Choice

If you want GRUB to remember your last choice add:

GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true
to /etc/default/grub and run sudo update-grub to apply new configuration.

Blender Player Python

If you encounter a problem with running Python [python] scripts on a “bare” Blender Player [blender], make sure that both PYTHONHOME and PYTHONPATH are set correctly to match your needs. You can also use native Blender python with a simple shell script:

#!/bin/sh
export PYTHONHOME="/path/to/blender/python/"
export PYTHONPATH=$PYTHONHOME"/bin"
/path/to/your/blenderplayer $@

[python] https://www.python.org/
[blender] https://www.blender.org/

bash filename and extenstion extraction

In case you need to separate a filename from an extension in bash here is a way:

filename=$(basename -- "$fullfile")
extension="${filename##*.}"
filename="${filename%.*}"

Migrating from MS Office365 to Googe Suite

If you want to move a business from Microsoft Office365 to Google Suite, there is a nice migration utility in Google Suite Admin Console that helps you transfer all accounts data from Exchange Web Server or IMAP.

In case you encounter an error here goes a list of error codes and troubleshooting guide [1].

I did a full migration by granting my temporary user Global Administrator right by current Admin user, then in Exchange Admin Console I had to grant myself an ApplicationImpersonation Admin Role (to access other accounts for migration). After the migration was complete I have rolled back my permissions to a minimum level.

[1] https://support.google.com/a/answer/6254288

binary file hexdump

Sometimes you need to quickly create a hexeditor like dump of a binary file. HEXDUMP is your friend. It may be a standard Unix application or Python module.

Unix hexdump use example:

hexdump -Cv file.bin
00000000  12 01 00 02 ef 02 01 40  28 0d 04 02 00 10 01 02  |.......@(.......|
00000010  03 01 12 01 00 02 ef 02  01 40 28 0d 04 02 00 10  |.........@(.....|
00000020  01 02 03 01 09 02 82 00  04 01 00 80 fa 09 02 82  |................|
00000030  00 04 01 00 80 fa 09 04  00 00 02 08 06 50 07 07  |.............P..|
00000040  05 82 02 40 00 00 07 05  02 02 40 00 00 09 04 03  |...@......@.....|
00000050  00 02 03 00 00 06 09 21  00 01 00 01 22 21 00 07  |.......!...."!..|
00000060  05 81 03 40 00 01 07 05  01 03 40 00 01 08 0b 01  |...@......@.....|
00000070  02 02 02 01 04 09 04 01  00 01 02 02 01 04 05 24  |...............$|
00000080  00 10 01 05 24 01 03 02  04 24 02 06 05 24 06 01  |....$....$...$..|
00000090  02 07 05 83 03 10 00 20  09 04 02 00 02 0a 00 00  |....... ........|
(...)

Python hexdump use example:

python -m pip install hexdump
python -m hexdump file.bin
00000000: 12 01 00 02 EF 02 01 40  28 0D 04 02 00 10 01 02  .......@(.......
00000010: 03 01 12 01 00 02 EF 02  01 40 28 0D 04 02 00 10  .........@(.....
00000020: 01 02 03 01 09 02 82 00  04 01 00 80 FA 09 02 82  ................
00000030: 00 04 01 00 80 FA 09 04  00 00 02 08 06 50 07 07  .............P..
00000040: 05 82 02 40 00 00 07 05  02 02 40 00 00 09 04 03  ...@......@.....
00000050: 00 02 03 00 00 06 09 21  00 01 00 01 22 21 00 07  .......!...."!..
00000060: 05 81 03 40 00 01 07 05  01 03 40 00 01 08 0B 01  ...@......@.....
00000070: 02 02 02 01 04 09 04 01  00 01 02 02 01 04 05 24  ...............$
00000080: 00 10 01 05 24 01 03 02  04 24 02 06 05 24 06 01  ....$....$...$..
00000090: 02 07 05 83 03 10 00 20  09 04 02 00 02 0A 00 00  ....... ........
(...)

Apple macOS 10.13 High Sierra Fail

Guys at Apple are either stoned or really working hard to make macOS as bad as Windows. macOS High Sierra (10.13) was probably designed by people that were really “high”. They removed TELNET utility that is second most valuable network testing utility after PING. Except for noticeable performance degradation glitches during video modeswitch and other failures macOS really gets close to Windows in its poor design decisions and obvious quality degradation for professional applications.. now I will hardly consider buying another overpriced MacMookPro..

fastboot too old problem

If you want to perform stock factory flashing of a Nexus device and you encounter “fastboot too old” error message, that means you need to update your local fastboot application to a newer version. One additional word would make this interesting error message self-explanatory..

Google Android Do Not Disturb Bluetooth Headset

I have just found and reported bug in Android [1] that allows Bluetooth Headset to ring even though the “Do Not Disturb” is set to most strict setting that should give no symptoms of incoming calls.

[1] https://issuetracker.google.com/issues/69537851

Added GOBI2000 support to FreeBSD U3G

I have added support for Panasonic ToughBook CF-F9 U3G GOBI2000 to FreeBSD U3G kernel module [1]. I have added firmware for Panasonic CF-F9 and HP EliteBook 2740p along with gobi_loader updates [2] that are required for 3G modems to work.

At first U3G module will create /dev/cuaU0 interface for QDL firmware load, then after successful firmware load device will reload itself to a modem mode and U3G module will provide additional /dev/cuaU0.* nodes for operations (/dev/cuaU0.2 is the AT command intarface).

In order for this modem to work on FreeBSD you also need to tune some configutation files:

  • /etc/devd.conf:
    attach 100 {
     match "vendor" "0x04da";  #adjust your device VID
     match "product" "0x250e"; #adjust your device PID
     action "/usr/local/sbin/gobi_loader -2000 /dev/cuaU0 /boot/firmware/gobi/";
    };
    
  • /etc/ppp/ppp.conf:
    default:
     set log Phase Chat LCP IPCP CCP tun command
     ident user-ppp VERSION
     set device /dev/cuaU0.2
     set phone *99\#
     set redial 5 10
     set speed 115200
     set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 5 \
               \"\" AT AT-OK-AT ATH OK ATZ OK ATE1Q0 OK \
               AT+CFUN=1 OK-AT-OK \
               AT+CPIN? READY-AT+CPIN=\"YOUR_PIN_HERE\"-OK \
               AT+CGDCONT=1,\\\"ip\\\",\\\"internet\\\" OK \
               \\dATDT\\T TIMEOUT 40 CONNECT"
     set timeout 20
     enable dns
     set ifaddr 10.0.0.1/0 10.0.0.2/0 255.255.255.255 0.0.0.0
     add default HISADDR
    

You now should be able to use your 3G modem connection with ppp -ddial, after you add your local user to the dialer group with pw groupmod dialer -m your_user_name. Remember to have U3G compiled in. Enjoy the Internets! :-)

[1] https://github.com/freebsd/freebsd/pull/115
[2] https://github.com/cederom/gobi_loader

Python Matplotlib macOS backend

Matplotlib is a nice Matlab-like environment for Python. If you encounter a backend related problem while using Matplotlib [1] on a Python Virtualenv [2], then you need to explicitly select one (i.e. backend : Qt5Agg) in a ~/.config/matplotlib/matplotlibrc (or directly in a matplotlib file located in current working directory) configuration file. Then remember to use modern interpreter and meet dependencies requirements. Example below:

$ mkdir ~/.matplotlib
$ echo "backend : Qt5Agg" >> ~/.config/matplotlib/matplotlibrc
$ echo "backend : Qt5Agg" >> matplotlibrc
$ python3.6 -m venv venv-mac-36
$ source venv-mac-36/bin/activate
$ which python
$ pip install matplotlib pyqt5

Now you can use Matplotlib inside created Python Virtualenv (assuming you had Python 3.6 and Qt5 [3] already installed on your system). Other backends are: TKAgg, GTKAgg, Qt4Agg, Qt5Agg, WXAgg [4].

[1] https://matplotlib.org/
[2] https://www.python.org/
[3] https://www.qt.io/
[4] https://matplotlib.org/faq/usage_faq.html

ARM mbed OS DAPLink pyOCD

It is my great honor to join Free-and-Open-Source ARM mbed [1] development team! :-)

[1] https://www.mbed.com