40:I[185,["/_next/static/chunks/3xnt26d00_zk-.js","/_next/static/chunks/1s-yni1uf2lwd.js","/_next/static/chunks/42spz6paskvb6.js","/_next/static/chunks/06x30xgfe6iur.js","/_next/static/chunks/3b4qrzgkt_l12.js","/_next/static/chunks/15lgs8s22dk5l.js"],"SendEmailButton"] 42:I[63625,["/_next/static/chunks/3xnt26d00_zk-.js","/_next/static/chunks/1s-yni1uf2lwd.js","/_next/static/chunks/42spz6paskvb6.js","/_next/static/chunks/06x30xgfe6iur.js","/_next/static/chunks/3b4qrzgkt_l12.js","/_next/static/chunks/15lgs8s22dk5l.js"],"AddToLibraryButton"] 43:I[29721,["/_next/static/chunks/3xnt26d00_zk-.js","/_next/static/chunks/1s-yni1uf2lwd.js","/_next/static/chunks/42spz6paskvb6.js","/_next/static/chunks/06x30xgfe6iur.js","/_next/static/chunks/3b4qrzgkt_l12.js","/_next/static/chunks/15lgs8s22dk5l.js"],"ShareButton"] 44:I[58016,["/_next/static/chunks/3xnt26d00_zk-.js","/_next/static/chunks/1s-yni1uf2lwd.js","/_next/static/chunks/42spz6paskvb6.js","/_next/static/chunks/06x30xgfe6iur.js","/_next/static/chunks/3b4qrzgkt_l12.js","/_next/static/chunks/15lgs8s22dk5l.js"],"ProcessEpisodeButton"] 45:I[45269,["/_next/static/chunks/3xnt26d00_zk-.js","/_next/static/chunks/1s-yni1uf2lwd.js","/_next/static/chunks/42spz6paskvb6.js","/_next/static/chunks/06x30xgfe6iur.js","/_next/static/chunks/3b4qrzgkt_l12.js","/_next/static/chunks/15lgs8s22dk5l.js"],"SignupCTA"] 3a:["$","div",null,{"className":"flex flex-wrap items-center gap-x-4 gap-y-1 font-mono text-[12px] uppercase tracking-[0.1em] text-[color:var(--fg-3)]","children":[["$","time",null,{"dateTime":"2025-05-12T13:11:00.000Z","children":"May 12, 2025"}],["$","span",null,{"aria-hidden":true,"children":"·"}],["$","span",null,{"children":"00:50:49"}],false]}] 41:T529,

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