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(2013) And also, BLE is more than Bluetooth in name only. There is the L2CAP layer and radio specs taken directly from Bluetooth Classic. There is also the fa

(2013) And also, BLE is more than Bluetooth in name only. There is the L2CAP layer and radio specs taken directly from Bluetooth Classic. There is also the fact that good or bad (I’ll let you guess) it is the same Special Interest Group that develops it.

fellerts 3y ago
[2013] is key. The information in this article is severely outdated, but the hacking is still cool I guess.
- dmitrygr 3y ago
  Back then, BLE-capable MCUs were rare and expensive. Now that you can get $0.10 MCUs out of china that speak BLE natively, this is no longer useful. I rarely take articles off my website, so it is still up. How it ended up on HN front page today, I am not sure.
dmitrygr 3y ago
> and radio specs taken directly from Bluetooth Classic False - modulations are entirely different. Channel hopping is done differently too. L2CAP is also quite cut down in many ways, having only the same 4 byte header in common. When I wrote this article (11 years ago), this was even more true than it is today (BLE did not even have the 2mbps mode yet)
- SV_BubbleTime 3y ago
  When I wrote the radio, I meant the radio. Not the bit timing and phase which is software. The PHY . It’s the same 2.4Ghz radio and same balun.
  - dmitrygr 3y ago
    Well, fuck, so is WiFi and three dozen other things. Means nothing. That’s what any 2.4GHz thing would have… Also bit timing and phase are NOT software. They are very much hardware state machines in all implementations.
    - SV_BubbleTime 3y ago
      There weren’t hardware here were they? Yes, WiFi uses the same radio, although IDK about balun.
      - dmitrygr 3y ago
        Even here bit timing is done by a hardware state machine. As is modulation.
      - nomel 3y ago
        > balun Why does that coil of wire matter? It's dictated by drive and antenna characteristics. It's an RF coupling efficiency thing, not really a BT/WiFi thing.
AshamedCaptain 3y ago
BLE literally started from a Bluetooth competitor technology that was later given to the Bluetooth SIG and renamed to BLE. It is literally Bluetooth in name only. Anyone who has read anything about them can tell they are almost like day and night.
- SV_BubbleTime 3y ago
  They aren’t the same people since 2009? It’s not the same L2CAP layer? TIL.
  - AshamedCaptain 3y ago
    Yes, it was given to the Bluetooth SIG in 2007ish, but it has not really evolved to be more classic/BR-like since then (or it would break compatibility). And no, it's not the same L2CAP layer -- it again shares the name and little else.

fellerts 3y ago

[2013] is key. The information in this article is severely outdated, but the hacking is still cool I guess.

dmitrygr 3y ago
Back then, BLE-capable MCUs were rare and expensive. Now that you can get $0.10 MCUs out of china that speak BLE natively, this is no longer useful. I rarely take articles off my website, so it is still up. How it ended up on HN front page today, I am not sure.

dmitrygr 3y ago

> and radio specs taken directly from Bluetooth Classic False - modulations are entirely different. Channel hopping is done differently too. L2CAP is also quite cut down in many ways, having only the same 4 byte header in common. When I wrote this article (11 years ago), this was even more true than it is today (BLE did not even have the 2mbps mode yet)

SV_BubbleTime 3y ago
When I wrote the radio, I meant the radio. Not the bit timing and phase which is software. The PHY . It’s the same 2.4Ghz radio and same balun.
- dmitrygr 3y ago
  Well, fuck, so is WiFi and three dozen other things. Means nothing. That’s what any 2.4GHz thing would have… Also bit timing and phase are NOT software. They are very much hardware state machines in all implementations.
  - SV_BubbleTime 3y ago
    There weren’t hardware here were they? Yes, WiFi uses the same radio, although IDK about balun.
    - dmitrygr 3y ago
      Even here bit timing is done by a hardware state machine. As is modulation.
    - nomel 3y ago
      > balun Why does that coil of wire matter? It's dictated by drive and antenna characteristics. It's an RF coupling efficiency thing, not really a BT/WiFi thing.

AshamedCaptain 3y ago

BLE literally started from a Bluetooth competitor technology that was later given to the Bluetooth SIG and renamed to BLE. It is literally Bluetooth in name only. Anyone who has read anything about them can tell they are almost like day and night.

SV_BubbleTime 3y ago
They aren’t the same people since 2009? It’s not the same L2CAP layer? TIL.
- AshamedCaptain 3y ago
  Yes, it was given to the Bluetooth SIG in 2007ish, but it has not really evolved to be more classic/BR-like since then (or it would break compatibility). And no, it's not the same L2CAP layer -- it again shares the name and little else.