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

15 posts under
Embedded electronics

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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OpenSTM32, OpenOCD and ST-Link debugging

I continue the evaluation of STM32 micro-controllers with a Nucleo-L053R8, a development board for the STM32L0XX family. I tried to use the OpenSTM32 package to use it with the Eclipse IDE and OpenOCD debugger and had to tinker a bit to be able to debug the target : the debug was working on Keil IDE...

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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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(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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