Notepad of a tinker, maker, hacker or whatever you call it :)

33 posts

There is not a lot to say, I like to discover new things mainly related to embedded electronics, but also mechanics or whatever I enjoy on the moment.

ESP32 / MQTT - BLE beacon tracker power by microPython

I am currently working with BLE beacons -only iBeacons for now- with Espressif's esp-idf libraries. The aims it to use the ESP32 as a gateway to published detected beacons to a MQTT broker. It was surprisingly easy and I will write something about that when the code will be more polished. By the way,...

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Important - Migration to Ghost 1.x

Migration to Ghost 1.0...

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How to setup an OpenWrt repository

I recently wanted to setup a repository for some custom OpenWrt packages for Respeaker. It seems that it is not so well documented, or at least, I did not found it and I have been helped on OpenWrt forum. Also, it is better to sign packages we go ! Prepare the repository Compile...

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STM32 - Custom USB HID device step by step

Step by step guide to do a custom USB HID device on STM32 using ST CubeMX. There is already one page addressing it but without any details for beginners. I will use my custom board based on STM32L0, but any Nucleo can be used by wiring a USB cable to 5V, GND, USB_D+...

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Custom USB HID device descriptor : consumer device (media) + keyboard

For a personal project I need media keys (play, volume, mute, ...) and a way to lock a computer under Windows (Windows+L keys). There is a lot of HID keyboard descriptors on the Internet, some are for keyboards + media but all contains at least one unused byte... Not a good thing for embedded systems...

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STM32 - Log and printf

I am currently using a library which heavily use LOG() functions, which requires to output text on printf() or one of its derivative. As I am also evaluating ST's HAL, I tried to use it instead of low level putc() function. First, we need to be able to use printf() in combination with HAL_...

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Designing an STM32L0xx board

After the STM32L151, I now focus on designing a board for STML052. Following are some notes about ST application notes I read to design an STM32L052 board. All documents can be found here. Datasheet, Reference manual, Errata sheet. Hardware development AN4467 - Getting started with STM32L0xx hardware development Hardware Voltage range, p6 Full speed...

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How to make a LoraWAN GPS tracker

What can you do in a rainy evening when you go to your hackerspace ? Take a NoteRF V2 PCB, a GPS, a battery and you can make a lora GPS tracker ! Solder the PCB Hand solder it or for lazy guys like me, order a $5 stencil from OSH Stencil. Prepare the rig, apply...

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