Linux kernel, Software

Linux block device driver

My article about character devices is quite popular so I decided to write something about another big class of the devices in Linux – block devices. This type of devices is used to access various types of storage hardware – hard disks, SSD and so on. Here I want to describe blk-mq based devices in modern (>= 5.0) Linux kernels…

Continue Reading

Electronics, Radio & antennas

Cheap single-component RF filters.

Low, Band and High – pass filters are one of the major components when working with RF. Depending on the application, filters can reduse out noise and unwanted signals, or to limit a transmit signal to a pre-specified frequency band in order to prevent interfering with other signals around. Here I want to describe how to build simple and cheap…

Continue Reading

Linux kernel, Linux system development, Software

C++ in Linux kernel

Linux kernel is written in C (and in Assembly in platform-specific portions) language. C language is only one allowed language to write kernel modules. And there is no problem, in most of the cases. But sometimes some stranger things may be required. Let’s see how to use C++ for the Linux kernel modules.

Electronics, Networking, Software

RS-485 practice and theory

Just built two RS-485 adapters (version 2) and decided to write little note about  RS-485 bus (and differential line) theory plus perform some testing of the devices. This material mostly interesting for newbies. In the end of this article you can find a funny way to test this devices đŸ™‚

Uncategorized

Hello HTTPS!

From this point my site is also available via https.   It was not mandatory, but in modern browsers http sites may be marked as ‘unsecured’ and ‘untrusted’. It may happen that in the nearest future all sites without encryptions will be blocked by default in every popular web browser. I don’t want to be badged as ‘untrusted’ or be…

Continue Reading