Electronics

Oliv'

nfcAudio is an MP3 player, with audio files selected thanks to an NFC tag placed on top of it. I build this two years ago for my kid so he can play by himself his preferred nursery rhymes and songs, it is still used at least once a week :-)

It is powered by an ESP8266 to play audio from a remote server, an I2S DAC driving the speaker and an NFC reader. Thanks to WiFi we can use it to play local files or any webradio stream from the Internet.

Oliv'

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

Anyway, by curiosity and to speed up development, I wanted to try microPython port to ESP32, and I did. Unfortunately, BLE support is not yet reliable enough and a lot of advertisements were lost with 4 to 6 beacons. This post is to keep track of my work and, hopefully, use in the future when microPython port will be more reliable :-)

Oliv'

For a 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 contain at least one unused byte… Not a good thing for embedded systems with constraint memory. Why? The descriptor can be found in USB-IF example (Appendix B) and describe a boot compatible keyboard. So unless you need your keyboard in boot menus, this byte can be dropped. Also, the example defines 6 simultaneous keys, I decreased it to three as I don’t need more.