4×4 direct drive RC car

For the first post in new category – electronics, I have decided to share a first glimpse of the project I’m working on for my diploma thesis. It is a model of electric vehicle, more precisely radio-controlled model car, driven by four microprocessor-controlled three-phase brushless (BLDC) electromotors. Rear motors are controlled by custom BLDC drivers based on PIC18 MCUs, front motors by custom driver based on STM32 MCU (my colleague’s work). These three communicate via SPI with the main computer – our beloved Raspberry Pi (currently model B with a mess of wires SPI level converter shield).

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Nokia N900 in the year 2015

Yesterday I had to deal with yet another issue the N900 got due to it’s aging set of applications and absence of company support. My university mail server dropped support of SSL, probably due to bugs recently found in SSLv3 protocol. Consequently, the N900’s default mail application silently ceased to check for new mail. This issue first appeared for gmail users and was solved by updating versions of Modest and tinymail in CSSU repositories. Maemo community indeed is amazing.

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Xfce Radeon power profile applet

If you are running Linux on a computer with older Radeon graphics card from HD 4000, HD 3000 or HD 2000 series GPUs, you have probably noticed issues with power profile setting. The open source “Radeon” driver handles power setting wrong and the usually recommended proprietary flgrx driver ceased to support older hardware. It is possible to use legacy radeon driver, but if you want to stick with the open source one, you should be able to manually adjust graphic card’s power settings.

There is a nice applet for KDE just ready for use. It seemed to be a bit unstable to me, but usually works. From a look at a user’s manual, it should be possible to recreate it for use in other desktop environments. How to do it in Xfce?
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Woo, first post. It was quite difficult to find a decent dark theme for WordPress. The search filters seem to be absolutely useless. The standard Twenty twelve theme does have a pretty nice dark setting, though.