Power Manager: Soft Power Control of USB and Low Voltage Devices

One frustrating aspect of firmware or kernel development on commodity hardware, such as cheap evaluation board or production devices, is the necessity of power-cycling the target device to reboot it every time the developer needs to load and run a new software build.

It sometimes happens that a development board is designed with proper management electronics to ease software development or automated testing, but in most cases the developer has reset the board manually, and sadly quite often reset buttons are unaccessible or just non-existent, requiring the developer to unplug and replug the power cable. If this ends up in your workflow and at the end of the day your fingers hurt, something is wrong.

This project is a small AVR/V-USB based board to control the power supply of development boards and other low voltage and USB powered devices. It allows to program a sequence of events for the output ports, has LED indicators for port status, and additionally provides power measurement on both USB and main power channels, and uses a bootloader for easy firmware upgrade… All in a solid and funny looking Hammond blue box!


https://fabiobaltieri.com/wp-content/uploads/2013/03/pm-intro1.jpg


https://fabiobaltieri.com/wp-content/uploads/2013/03/pm-intro2.jpg

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HP Wi-Fi Direct Mouse on Linux

In my last post I took apart an HP Wi-Fi Direct mouse based on the OZMO2000 controller from Ozmo Devices.

OZMO based devices are officially supported on Windows 7 platform only, rendering them completely useless as nobody uses Windows anymore… right? Well, it turns out most of the code to use them in Linux is already in place, just waiting to be enabled!


https://fabiobaltieri.com/wp-content/uploads/2013/02/hp-wifi-mouse-linux.jpg

Wi-Fi direct support in Linux is quite young and still considered as experimental, so read on if you dare to try!

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