Now the operating system. Take two with Armbian.
Get the OS image Armbian_5.25_Nanopineo_Ubuntu_xenial_default_3.4.113.7z at [1].
Write the image to the SD-card (4GB min):
sudo dd if=Armbian_5.25_Nanopineo_Ubuntu_xenial_default_3.4.113.img of=/dev/mmcblk0 …
Now the operating system. Take one with the official image from FriendlyArm.
Get the OS image nanopi-neo-ubuntu-core-qte-sd4g-20170204.img.zip at [1].
Write the image to the SD-card (4GB min):
sudo dd if=nanopi-neo-ubuntu-core-qte-sd4g-20170204.img of=/dev/mmcblk0 bs …
Cute little ARM board (inner active ingredient) + Tiny 3D-printed housing (color plastic hull) + Transparent sticker (attractive branding) = your new medication for pretty printing.
The Nano Pi Neo is a cheap Chinese ARM board with everything needed (Ethernet, On-the-Go USB) and a tiny 40x40mm form-factor [1].
The …
How to serve a website by merging multiple base folders?
mod_alias is the answer! [1]
/opt/ina/all/www/
term/www/
cli/www/
pp/www/
dbg/www/
alias.url += ( "/all" => "/opt/ina/all/www/" ) alias.url += ( "/term" => "/opt/ina/term/www/" ) [...]
/etc/lighttpd/conf-available/50-inaterm.conf:
server.modules += ( "mod_alias" ) alias …read more
How to create a systemd-friendly QWebSocket server?
Surprisingly, there does not seem to be any official Qt documentation for this use-case. Enjoy.
The keyword here is socket-based activation. [1]
systemd will create the socket first and listen to incoming connections. On first incoming connection, the …
What is this timestamp in each kernel printk message?
Quote from [1].
Printk-time uses the routine sched_clock() in the kernel. On some platforms, sched_clock() only has a resolution of 1 jiffy (which may be 10 milliseconds or longer). This means that you will only see the time increment at this …read more
Prepare a Debian virtual image to build packages.
Get the netinstall 248MB image (e.g., debian-8.7.1-amd64-netinst.iso) at this address [1], and start a new virtualbox machine.
Only need a minimalistic system.
Ready!
A short introduction …
Highly insecure!
Create a user with a password, and delete it later ([1]):
root@inabox:/home/ina# adduser test [...give a password...] root@inabox:/home/ina# passwd -d test passwd: password expiry information changed.
In /etc …
Loop over all the members of an enumeration.
#include <iterator>
// Inspired from http://codereview.stackexchange.com/a/57699
template<typename T, T... args>
struct EnumIterAll
: public std::iterator<
std::input_iterator_tag, // iterator_category
T, // value_type
std::ptrdiff_t, // difference_type
const T*, // pointer
const T& // reference
>
{
static constexpr T values[] = {args...};
static constexpr std …Initial example for setting a kernel tracepoint and forward the trace output over DLT (Autosar Diagnostic Log and Trace).
This example is taken straight out of the Linux kernel documentation at [1]. For details about the kprobes internals, see [2].
# The tracing facility is in the …
https://wiki.linuxfoundation.org/images/1/1c/Network_data_flow_through_kernel.png https://wiki.linuxfoundation.org/networking/kernel_flow
perf uses kprobes/uprobes for dynamique tracing.
perf for Performance counter …
read moreHow do Linux kernel probes (kprobes) work
Everything below comes from reading kprobes.txt at [1].
There are kprobes and jprobes. jprobes are specialized kprobes for function calls, making it easier to get the function parameters. It is usually useful to filter function call traces according to the value …
What else is happening again?
(process:704): GLib-WARNING **: poll(2) failed due to: Invalid argument.
$ sysctl net.core.somaxconn net.core.somaxconn = 128
$ find /usr/include -name socket.h /usr/include/asm-generic/socket.h /usr/include/linux/socket.h /usr/include/x86_64-linux-gnu/bits/socket.h /usr/include/x86_64-linux-gnu …
But wait! What happens when I use Chinese input? ...types CTRL+Space and start composing... Oh shit!~ [1]
Capturing key strokes is nice, but it does not support virtual keyboard like on tablet or smartphones and more advanced input methods such as Chinese/Japanese or other writing systems.
The problem …
read morestd::string l;
// Read lines here
while(std::getline(std::cin, l))
{
// Send Unicode string
emit newLine(QString::fromStdString(l));
}
This works because \n (newline) is a single byte in UTF-8.
char c;
// Read bytes here
while(std::cin.get(c))
{
// Send Unicode single …A story which begins on the keyboard, goes through a pseudo-terminal, and ends up on the screen.
Now that you love ptypipe (see previous post), we are ready to pipe everything and finally control gdb:
$ makefifo input.cli $ python ptypipe.py "" "gdb -q" < input.cli | myGreatControlProgram > input.cli
You can pipe commands to gdb, but how to have auto-complete on those commands?
A initial little try is promising, we can pipe commands to gdb:
~$ echo "show endian" | gdb -q (gdb) The target endianness is set automatically (currently little endian) (gdb) quit
The command show endian was …
Questioning about the "target triplet" <CPU>-<vendor>-<OS> used by the GNU build system to describe a target
When building gdb targeting a different platform, one must choose --host, --build, and --target parameters.
The target parameter has the following format [1]:
<CPU>-<vendor>-<OS>
You can get the target of …
read moreMany websites host HTML rendering of man pages. How to make them yourself?
Stackoverflow always has an answer for those questions [1].
A tool without many dependencies is mandoc [2], and of course, it has its mandatory HTML man page there [3].
./configure make ./mandoc -Thtml -Ostyle=mandoc.css ../man-pages-4 …read more
Beware link wall ahead
Stumbling upon this page [1] ended up in a massive recurssive tree search. A stack of links where kept here.
Why not profiling your application by sampling backtraces using gdb? This intuitive idea is easily adapted to remote debugging as well. [2]
If …
gcc has an extensive documentation [1] in the texinfo format (.texi file extention). texinfo [2] can be converted into many different output formats, such as HTML, PDF, ...and generic XML.
I would like to write a quick-and-dirty script to extract the description of each command-line argument of gcc. I could …
read moreHow to record your screen into an animated gif with precise position and size?
I would like to create an animated gif with a size of 800x600px. The canva should contain a web browser in the top half, and a command-line terminal in the bottom half.
Random notes
Download the "Raspbian Jessie Lite" image: https://www.raspberrypi.org/downloads/raspbian/ Writing the image: https://www.raspberrypi.org/documentation/installation/installing-images/linux.md sudo dd bs=4M if=2016-05-27-raspbian-jessie.img of=/dev/sdd connect a screen on HDMI and check the My IP address is xxx To …read more
The Bosch XDK is a development platform centered around a set of Bosch sensors.
It features an EFM32 ARM Cortex-M3 based microcontroller.
| [1] | Bosch XDK, homepage, http://xdk.bosch-connectivity.com |
| [2] | Bosch XDK, API and docs (doxygen), http://xdk.bosch-connectivity.com/xdk_docs/ |
| [3] | Bosch XDK, Extention port pinout, http … |
Price: ★☆☆ Taste: ★★★ Difficulty: ★★☆
Yocto [1] is now a common solution for creating automated build of custom GNU/Linux images for …
Little benchmark of the CommonAPI example on a Raspberry Pi 2
CommonAPI [1] is an open-source (Mozilla Public License 2.0) developped by BMW.
It enables to abstract communication middleware (i.e., IPC) such as D-Bus [2] or SOME/IP [3].
The E01HelloWorld tutorial is found …
How to debug an Atom processor over JTAG?
Official presentation of the "Intel JTAG debugger" is [1].
The standard Intel debug port is the 60-pin XDP (eXtended Debug Port). It extends JTAG with additional signals. This port also has a lower pin count variant: the 31-pin XDP-SSA (Second Side Attach …
read moreI don't want a fully fledged Eclipse project or depend on heavy Eclipse for anything.~
I don't know if you have the same feeling, but it doesn't look like a good idea to depend on one heavy tool for anything in your electronic project. Having easy-to-understand scripts for building or …
read moreThe USB specs are pretty large.
USB 2.0 specs [1]. Explanations [2].
Good description of the protocol [3].
Another source [4].
USB communications can be spyed with:
Software Wireshark (example video there [5]).
Hardware OpenVizsla An Open-source FPGA-based USB sniffer [6]... based of the Xilinx Spartan …
OpenOCD does know the STM32F446?
Open On-Chip Debugger 0.8.0 (2014-05-10-23:20)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.sourceforge.net/doc/doxygen/bugs.html
Info : This adapter doesn't support configurable speed
Info : STLINK v2 JTAG v17 API v2 SWIM v0 VID 0x0483 PID 0x3748 …
read more
I am trying to motivate me to do this project for months now, and I looked like nobody cared about it.
Thanks to Google webmaster tools (not Google Analytics, I care about your privacy, dear reader), I was able to see which other site linked my blog. Reddit does it …
read moreThe goal: The memory controller can be used to generate a "generic" 16-bit parallel data stream with clock. Address generation will be disregarded, as well as other control signals dedicated to memory chips.
It must be noted that the STM32F40x and STM32F41x have the FSMC (static memories), while the STM32F42x …
read moreSpartan-6 maximum JTAG clock is 18-33MHz according to "Table 3: Maximum JTAG Clock Frequencies" in [DS593] (v1.4, p. 8).
The Spartan-6 at speed grade -1L is limited to 18MHz, while other speed grades (-2, -3N, and -3) allows a TCK of 33MHz. See "Configuration Switching Characteristics" in [DS162] (v3 …
read more...after finding a shortcut on the JTAG adapter board and burning an FPGA by connection the power supply the wrong way, in the morning, everything finally works together.
Microcontroller debug. access over SWD. The STM32F4x CPU is found:
Open On-Chip Debugger 0.8.0 (2014-05-10-23:20) Licensed …
Quick post about OpenOCD and flash erase error -304.
Getting the following error:
Open On-Chip Debugger 0.8.0 (2014-05-10-23:20)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.sourceforge.net/doc/doxygen/bugs.html
Info : This adapter doesn't support configurable speed
Info : STLINK v2 JTAG v17 …
read more
Buying a cheap analog multimeter at Conrad [1]... and having to repair it right out of the box!
The discret wire connecting the battery to the voltmeter line was broken. Fortunately, this analog multimeter is so simple that you can reverse engineer it easily and find the issue.
[1 …
Inside of the FLRe first complete prototype.
The microcontroller and FPGA boards are inserted facing each other in the (upper and lower) PCB guide grooves of the enclosure.
read moreAfter testing many random stuff, I decided to give a try to Single Wire Debug (SWD) instead of JTAG. The STM32F429I-DISCO demo board embed a ST-Link V2 which can be used for other boards as well.
According to ST datasheet, the JTAG and SWD port are shared:
The ARM SWJ-DP …read more
Let's desolder the microcontroller?
Damn, this is just standard solderwire, nothing to do with the desoldering alloy and its low melting point. Ordering mistake... (u_u)
Result, went a bit medieval on the poor chip...
read more
The FLRe p1 microcontroller board is finished and ready for tests. First test? Trying to get the CPU chip id over JTAG.
The target board uses a custom 0.5" JTAG header. Some home-made adapter are needed.
Open On-Chip Debugger 0.8.0 (2014-05-10-23:20) Licensed under GNU GPL v2 …read more
Last year, I made a post about the bit-banging capacities of the STM32F1 (ARM Cortex-M3) microcontroller. Here are some comparisons with the STM32F4 (Cortex-M4).
The STM32F4 runs at 168MHz CPU clock.
Because my oscilloscope only goes up to 50MHz, I made a …
This post is about using OpenSTM32 plugins for Eclipse and STM32CubeMX with Ubuntu 14.10.
OpenSTM32 [1] is a project aiming at making embedded development for STM32 microcontroller easier with Eclipse. "System Workbench for STM32 - Bare Metal Edition" features are described at [2]. There is an all-in-one installer for …
The hardware of the FLRe microcontroller board is ready!
For a detailed picture, see: https://vjordan.info/flr/p1/flre_p1_micro_board_details_rev1.jpg
read more
| [1] | Ascel Electronic, AE20204 High Precision LC Meter, http://www.ascel-electronic.de/kits/6/ae20204-high-precision-lc-meter |
