Author: Jan

Programmable DC/DC

One of the ideas I am playing around with is to make my own programmable DC/DC PSU based on a MCU. The technique is very similar to a driver channel on a motor by generating a PWM signal. To get a DC out you add filter(s). If you have 48V and 50% PWM duty the…

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Motor Controllers

These are the 4 different motor drivers I have made so far. The smallest (at left) is capable of 24V @2A. It uses DRV10983 and one of the smallest STM32’s. I got it working, but I had some trouble controlling the logic to behave. The second one uses a DRV8313 that basically is 3 x…

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Wifi Hat Working

Replaced ESP32 on the failing Hat and Wifi worked. Seems like I had my first ever failing ESP32 module. The Wifi Hat is No 2 from top. This stack includes (from top): 7 x Stepper Hat ESP32 Based Wifi Hat XPortHub XPortHub Raspberry PI 3A+ I have 2 USB ports connected here and both show…

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Unipolar Stepper Logic

This is the diagram of an Unipolar Stepper Motor with the 5-wire connector at right. The most used Unipolar stepper is the 28BYJ-48-5V pictured below and this is the target of my 7x5WStepper Hat. This is a high quality/low cost stepper available for < 2.-USD. I purchased one for test and was quite take by…

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HAL

All MCU vendors will deliver some C code they call “HAL”, while I call that Low Level Drivers (or BSP – Board Support Package) and implement my own HAL (Hardware Abstraction Layer). A proper HAL need to abstract from hardware and secure portability of code. But, most important is that I want to write source…

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Auto Generated Doc

I use CubeMX to verify the wiring of my Boards and one of the features I like is that it auto-generate a report like the one below. Just click on the link and you can see the full report of the 7xStepper Hat. 7x5WStepper This is basically information that is very handy to have available…

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MCU Tester

My STM32 Tester finally arrived, and 12 rejected MCU’s which is ca 40% of all STM32F405’s I had is the result. The sent me a different tester than I ordered, but it did the trick. One MCU broke under testing as well. 10 x STM32F405RG cost va 45.- USD from China and ca 90.- USD…

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