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Comment by bigiain | Hacker News Reader

I had a Timex Data Watch over 30 years ago.

https://en.wikipedia.org/wiki/Timex_Datalink

It'd transfer phone numbers and calendar entries to the watch by blinking the screen of your computer. Kinda a 1 pixel version of this.

(I wonder where that ended up? From memory I threw it in a drawer when I finished the Windows 95 project I'd been working on, and switched to Mac. There was no Mac software to talk to it.)

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I have seen digital audio gear that solved firmware transfer like that. You basically go to a website on your phone and it flickers the screen and you hold it in front of a photosensitive bit of the device that needs to be updated for 20 seconds and done.

If your firmware is small enough to fit that model, it isn't a bad variant. Beats downloading a file, transferring it to a USB drive, sticking that in,...

That'd be a few 100 bytes at best… what firmware fits into that?

100 bytes in 20 seconds would only be 40 bps. Surely you can do better than that even using only one bit symbols (off/on).

With a flashing phone screen? 120Hz tops, right?

If only they had a clean digital way of getting data into the system.

Listen, you do not want your firmware to be updated by playing a FLAC file.

FLAC? That shows some degree of advanced technology that I would assume the original device in question does not have.

It's "digital audio gear". It receives uncompressed PCM, which could come from your computer playing a FLAC.

right, so a very specific case of playing FLAC via an external device, not on the system itself. Ok, that makes more sense. Still don't get what the issue is. Put the device in the correct mode and play from whatever digital input or playback (CD, DAT etc) the system already has.

Okay, if there's a button you have to hold to enable firmware update then it's more sensible.

Probably still wouldn't want to use digital audio input though. Although it's a perfect digital stream, it's been processed in analog-like ways before it gets to the device - such as filtering and volume changes. So you'd still want to use a modem protocol over it.

Especially if it's a recording of Rhythm Nation.

Psion Series 5 and other PDAs had infra red (IrDA) ports for 'beam'ing contacts, transferring files, printing, etc.

1998 - https://groups.google.com/g/comp.sys.psion.misc/c/oFtTHyx6IR...

1994 - https://en.wikipedia.org/wiki/IrDA

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