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MicrosoftShilltoday at 2:55 AM3 repliesview on HN

Is it really as easy as you say? I have one of these Casio watches and plenty of spare Claude credits. Wouldn’t mind doing this but no idea where to begin.


Replies

gregsadetskytoday at 4:23 AM

Responding to you and @thewhitetulip

If you ask Claude how to do it, it might already give you some strategy that's reasonable (at least, it's good to see what it thinks)

Make sure to use Fable, and preferably have the Max plan (or plenty of credits)

LLMs can do very good work when they're unattended and optimize towards a goal that's unambiguous / for which you have a reference.

Generally speaking, in hardware, this means having a "rig" ie a testbed where the AI can send commands, observe output, and iterate on its own. You want autonomy, not babysitting (as much as possible)

In the case of this Casio watch, I would start by giving Claude Code context on what you're trying to achieve (read&decode messages sent probably over BLE, reverse engineer the protocol, get to a point where it can send valid messages itself). The goal should be a python/command line tool that can sniff packets, decode them, and send them. (step by step, starting with sniffing)

Get the nRF52840 USB dongle mentioned. Have Claude Code talk to the dongle. Ask it to list devices it sees. Ask it to see/detect the Casio watch. Use the proprietary Casio app and ask CC to record the sequence and decode the messages (explaining to it what you did in the app)

Also: have it do research - has this protocol been cracked/documented before? Is there an Android app for this Casio app which could be decompiled (usually more easily than the equivalent iOS app)?

Reach out if I can help - my offer for a dongle stands for anyone who wants to do this! It looks like a cool watch, it shouldn't be held hostage. :-)

show 2 replies
thewhitetuliptoday at 3:05 AM

Even I am curious about how people are doing this

bowsamictoday at 4:23 AM

> Wouldn’t mind doing this but no idea where to begin.

Literally just ask Claude where to begin