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This is the first in a series of posts exploring how to build a smartwatch in 2025! Plus a dive into my box of ancient hardware projects.

Special guest - Jingming, CEO of SiFli

SF32LB52x reference guide: https://drive.google.com/file/d/1FV5-n6thM8XkzVQeAap2eJv97sCO_NrG/view

Github: https://github.com/OpenSiFli

Get a new PebbleOS watch!

https://store.rePebble.com

0:00 Intro

0:55 What makes up a smartwatch?

1:50 Tour of my Ancient History box

5:27 Movie magic in the first Pebble Kickstarter 😅

6:19 Constraint maximization

8:22 Hardware subsystems

9:23 Picking components...

10:06 How do you pick a chip?

12:33 What is an MCU?

15:30 Core 2 Duo MCU

16:43 Core Time 2 MCU reveal!

19:15 Why we picked SiFli SF32LB52J chip

21:20 Interview with Jingming - SiFli CEO

21:37 Why did you start a silicon company?

22:30 What's your background?

25:20 How does one start a silicon company?

32:21 What was your insight that drove SiFli?

35:30 SiFli and open source (no NDA needed)

37:30 What does your dream smartwatch look like?

41:15 Favourite gadgets

44:00 Future of MCUs

47:30 Favourite embedded hack