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


30 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.

Designing an STM32L15xx board

Following are some notes about ST application notes I read to design an STM32L151 board. All documents can be found here. AN2606 - Microcontroller system memory boot mode AN2606 - Microcontroller system memory boot mode Bootloader in USART1 or USART2 Unused RX (USART1 or 2) pin must be pulled and not left floating AN3216...

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Android - Send a HTTP(S) POST request

As a part of my ioPush Android application, I needed to send a POST request to a secure server. I found some example over the internet but nothing parametric. Here is my code, with optional basic HTTP authentication and headers: Packages importation // Required for httpPost() method import; import;...

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NoteRF - Sensors schematic and layout

Finally I published it, sources of my wireless sensors are available here. For the record it has: ATMega328 RFM69 wireless chip All analog and digital ports 3.3V regulator Battery tension can be sensed through A7 Footprint for DS7505 temperature sensor FTDI and ISP connectors...

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(Not so) industrial reflow process

I wanted to try if a 100% DIY process to reflow a small batch of boards. For about 10 boards it is cheaper to hand solder them than ordering a stencil, but I was wondering if it can be faster to manually cut a stencil and reflow the boards on a frying pan. Stencil...

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Citroen C4 - Steering wheels buttons repair - Réparation des boutons du régulateur

As I did not found any help over the Internet on that subject, but read that other people have this problem I publish here why the buttons of my cruise control were not working. I started one year ago when suddenly all the buttons were swapped: Minus was not working anymore Plus was acting...

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Use Sigfox, Arduino (Akeru), PHP and callbacks

A friend of mine asked me for some help on an Akeru device, it is an Arduino + Sigfox modem. After few tinkering we succeed to do what he wanted and share it : gather some sensors data and collect it in a PHP webpage. The Arduino code is quite easy thanks to the Akeru library...

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HAProxy - How to use Let's encrypt certificate

Thanks to Let's Encrypt program, we can now generate free SSL certificate. I used the beta program with success, but now I tried on another server running through HAProxy. This is a trick to combine certificate, chain and private key in order to be loaded by HAProxy :) cat cert.pem chain.pem privkey.pem...

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