Arduino selection (or other microcontroller)

[L4g0]

We will need an microcontroller small enough to fit in a wrist watch and capable of handling all the I/O need.

[L4g0]

@L4g0 Check https://www.dfrobot.com/product-1259.html

[L4g0]

@L4g0 https://forum.arduino.cc/index.php?topic=432323.0
https://www.google.es/amp/s/amp.reddit.com/r/arduino/comments/43uzz8/what_is_the_smallest_possible_bluetooth_capable/

Aquí dan un par de opciones que parecen viables también, aunque por lo que veo la gente usa bastante la primera que pasé

[David-Estevez]

Yo diría, por lo usado que es en los círculos makers y del IOT, el ESP32:

https://www.aliexpress.com/item/ESP-32-ESP-32S-Development-Board-WiFi-Bluetooth-Ultra-Low-Power-Consumption-Dual-Cores-ESP32-Board/32844181786.html

[David-Estevez]

Arduino + BLE + (creo) lipo charger: https://www.seeedstudio.com/Blueduino-Rev2--Arduino-compatible-pius-BLE-CC2540-p-2550.html

Docs: http://wiki.aprbrother.com/wiki/BlueDuino_rev2

[L4g0]

https://www.thingiverse.com/thing:2628277 This guy made a similar project using this Bluetooth Module: https://www.sparkfun.com/products/retired/14154

Give it a look, dudes

[L4g0]

Maybe the ATtiny85 is a good idea, small microcontroller. It does not have Wifi/BT though.

[JorFru]

I can provide an Attiny 85 with proggraming board for testing purposes and first prototypes.

Check this guide if you want to learn how to program this microcontroller.

[David-Estevez]

Display + encoder will probably use all the pins available in ATtinny85

[L4g0]

Yes, we can use some kind of mux, but idk.
The best idea is to stick to the ESP32, I need to explore how to use it without the development board (nodeMCU), imo that is so big for a wearable

[David-Estevez]

My approach would be:

1. Make it work with whatever board we have at hand (better if it has BT/WiFi)
2. Once it's working, make it small

Otherwise, challenges and problems arising from (2) will also affect (1) and it will be twice as hard to debug.

[brunorchaves]

Hi! I'm doing this exactly same project right now. I'm using an Arduino Leonardo and a bluetooth module. I don't now if the Esp3's wifi circuit is necessary and this module is actualy very big. Anyway I have both microcontrollers here, and once the project was already started with ESP32 I will also use it . My idea is to design a small pcb for it in the future to reduce the size, but it is not very important right now. Let's make progress on this project!!