Author: Jan


HAL (Hardware Abstraction layer) is an interface between “normal” user modules and actual hardware. It makes hardware access easy and portable, it also gives us a layer where we can write optimized, hardware specific code if we need to. We will add more HAL classes as we go. ETC (Elapsed Time Clock) count the time…

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The picture show a classic MPU9255 breakout board found on ebay for < 5.- GBP. MPU9255 provide both I2C and SPI interface and a total of 9 sensors (3 axis Gyro, Magnetometer and Accelerometer). In our case we will use the SPI ports Connected to STM32. I am not sure if I should add a…

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DIY Spider Robot

This robot prototype uses a simple wooden box as body and 6 pan&tilt camera holders with  a total of 12 servos to move around. The picture is a prototype to test the concept. I initially used a 5.2Ah LIPO but the total weight on the servos was getting a bit much, so I dropped down…

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Adding a LED

Looking at my Rx breakout board I realize I need to add a LED for status. I don’t like wasting pins, but not having a Status led will be a pain.

Rx Breakout Schematics

This is the current revision 1.0 of the Rx breakout board. I am trying to find a decent way to display schematics, but the EDA I use is a bit limited in that respect. I am not going to mention what I use because I intend to change that to an open source EDA soon.

Standard SWD Adapter

This SWD Adapter was created to avoid the need for 2.54 pitch connectors on the boards and to have a standard way of supporting a debug environment with the mini version of ST-Link v2. The form factor above is made narrow to allow it to be connected to a Hat that is in the middle…

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STM32FxxxRx breakout board

This is mostly for my own usage. I have a strong preference for wiring and testing on bread boards before I order PCB’s. Sometimes it saves you 2-3 extra rounds to be able to do simple concept testing. I have plenty of breakout boards with STM32, but I fancied my own with my own SWD…

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Raspberry PI Hat’s

I have drafted a few Hat’s so I am adding an overview just to move content into the new blog. Zero GPIO was my first Hat. This is the new, revised version that I have not ordered yet. I am waiting to verify SPI interface before I order new Hat’s. For the Zero I actually…

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