6 ms·

Teardown of the Microsoft Band

76 points by schappim 12y ago

at-fates-hands 12y ago
I just got one of these and like a lot so far. The only Achilles heel for this is getting the data out and doing some real analysis of what your sleep cycles are, how your fitness levels trend, etc. Hopefully in the near future, they will come out with something, but thus far, the data you see is quite limited.
- lazyjeff 12y ago
  I managed to extract the raw minute-by-minute data from the Band using some hacky tricks. I was thinking of posting a howto, but trying to check if it runs into problems with the CFAA/DMCA. Might post something tomorrow after making sure it's legally sound.
  - at-fates-hands 12y ago
    Nicely done. I'll keep my eyes peeled or you can IM me when you get it up somewhere. Looking forward to it.
    - lazyjeff 12y ago
      I just submitted it to Hacker News in new submissions
  - schappim 12y ago
    do it!
  - hayksaakian 12y ago
    I would upvote it
  - lhl 12y ago
    I'm curious whether you decoded the binary protocol/blob or have just been poking at the API (where just about everything is pretty convenient JSON). I've done the latter but haven't broken out my Ubertooth yet for the former. Re: DMCA - there's a reverse engineering carve-out for interoperability. While I guess MS could abuse either CFAA/DMCA to slap down RE, it seems like it'd be a pretty bad PR move.
    - lazyjeff 12y ago
      I think what I was doing is the latter. Anyways, I just posted the writeup if you want to swap notes.
      - lhl 12y ago
        A lot of my notes aren't super well organized (and wouldn't make sense w/o scrubbed captured flows) but I just posted a comment on your post thread talking about the BTLE as well as the remote API stuff.
userbinator 12y ago
For comparison, the Nike+ FuelBand teardown: http://www.youtube.com/watch?v=7xdajSS_cOU http://www.youtube.com/watch?v=7xdajSS_cOU (Warning: very lengthy and detailed, contains some humour.)
tdicola 12y ago
Interesting to see a Cortex-M4 on board, certainly no way it's running Windows. Maybe they have some simple RTOS?
- kabdib 12y ago
  Not really an RTOS. I hear it's more an "event loop and some interrupt handlers," much like the firmware in the Kinect. (We went through a "we need an RTOS" phase on the Kinect. Eventually we ditched the thread stuff we wrote, which made things a lot simpler -- if you don't absolutely have to have threads and can get away with computing stuff in a main loop, then do that. Threads introduce all kinds of synchronization and inconsistent execution time nonsense that you should avoid if you can).
  - reddiric 12y ago
    I think of a time slicer as an rtos - a simple one :)
  - Marcus10110 12y ago
    fascinating. I assume that was the first kinect. Was the vision processing separated from the USB interface in different chips? Sounds like a fun project.
    - kabdib 12y ago
      The 1.0 Kinect is several processors: - A "DSP" based camera system that just does transfers from the sensor system to USB, and that does some other monitoring and housekeeping. It does no vision processing, it's just pass-through of video from the chips to the host. - An ARM-based audio system that handles mic data, runs an echo cancelation algorithm against host-provided speaker data, and provides the raw and echo-canceled mic data to the host. Early Kinect versions used yet another processor for managing the tilt motor and accelerometer. This stuff was move to the ARM later (that a tilt-motor processor existed in year 1 units is a fine example of team structure affecting product structure). All of these CPUs have their own USB interfaces, and there's an internal USB hub so there's only one wire going to the host. :-) None of these chips use an RTOS; that would just get in the way. The vision processing is done on the host, where you have heavy lifting capability with GPUs and tons of memory and so on. Doing that processing on the camera would quite expensive in terms of hardware and power, and wouldn't be able to adapt as well to new algorithms.
Animats 12y ago
Do not remove the Loyalty Bracelet. http://www.yuwanmei.com/products#4 http://www.yuwanmei.com/products#4
- blinduck 12y ago
  Wow, is this site an actual business or some kind of parody?
  - Animats 12y ago
    That site is run by The Onion, which, for a few weeks, claimed to have been bought out by Yu Wan Mei Salvage Fisheries and Polymer Injection Corporation. Any time is Fish Time!
didgeoridoo 12y ago
Anyone else have trouble not automatically translating "LiPo" battery as "Lithium/Polonium" in their heads? That would be a bad battery.
minthd 12y ago
It seems like some components are missing, for example the gps and and microphone.
rasz_pl 12y ago
-failed to remove qrcode sticker from big chip? -failed to identify gyro/accelerometer/compass chips ifixit they are not, but its a good start

76 points by schappim 12y ago

I just got one of these and like a lot so far. The only Achilles heel for this is getting the data out and doing some real analysis of what your sleep cycles are, how your fitness levels trend, etc. Hopefully in the near future, they will come out with something, but thus far, the data you see is quite limited.

lazyjeff 12y ago
I managed to extract the raw minute-by-minute data from the Band using some hacky tricks. I was thinking of posting a howto, but trying to check if it runs into problems with the CFAA/DMCA. Might post something tomorrow after making sure it's legally sound.
- at-fates-hands 12y ago
  Nicely done. I'll keep my eyes peeled or you can IM me when you get it up somewhere. Looking forward to it.
  - lazyjeff 12y ago
    I just submitted it to Hacker News in new submissions
- schappim 12y ago
  do it!
- hayksaakian 12y ago
  I would upvote it
- lhl 12y ago
  I'm curious whether you decoded the binary protocol/blob or have just been poking at the API (where just about everything is pretty convenient JSON). I've done the latter but haven't broken out my Ubertooth yet for the former. Re: DMCA - there's a reverse engineering carve-out for interoperability. While I guess MS could abuse either CFAA/DMCA to slap down RE, it seems like it'd be a pretty bad PR move.
  - lazyjeff 12y ago
    I think what I was doing is the latter. Anyways, I just posted the writeup if you want to swap notes.
    - lhl 12y ago
      A lot of my notes aren't super well organized (and wouldn't make sense w/o scrubbed captured flows) but I just posted a comment on your post thread talking about the BTLE as well as the remote API stuff.

userbinator 12y ago

For comparison, the Nike+ FuelBand teardown: http://www.youtube.com/watch?v=7xdajSS_cOU http://www.youtube.com/watch?v=7xdajSS_cOU (Warning: very lengthy and detailed, contains some humour.)

tdicola 12y ago

Interesting to see a Cortex-M4 on board, certainly no way it's running Windows. Maybe they have some simple RTOS?

kabdib 12y ago
Not really an RTOS. I hear it's more an "event loop and some interrupt handlers," much like the firmware in the Kinect. (We went through a "we need an RTOS" phase on the Kinect. Eventually we ditched the thread stuff we wrote, which made things a lot simpler -- if you don't absolutely have to have threads and can get away with computing stuff in a main loop, then do that. Threads introduce all kinds of synchronization and inconsistent execution time nonsense that you should avoid if you can).
- reddiric 12y ago
  I think of a time slicer as an rtos - a simple one :)
- Marcus10110 12y ago
  fascinating. I assume that was the first kinect. Was the vision processing separated from the USB interface in different chips? Sounds like a fun project.
  - kabdib 12y ago
    The 1.0 Kinect is several processors: - A "DSP" based camera system that just does transfers from the sensor system to USB, and that does some other monitoring and housekeeping. It does no vision processing, it's just pass-through of video from the chips to the host. - An ARM-based audio system that handles mic data, runs an echo cancelation algorithm against host-provided speaker data, and provides the raw and echo-canceled mic data to the host. Early Kinect versions used yet another processor for managing the tilt motor and accelerometer. This stuff was move to the ARM later (that a tilt-motor processor existed in year 1 units is a fine example of team structure affecting product structure). All of these CPUs have their own USB interfaces, and there's an internal USB hub so there's only one wire going to the host. :-) None of these chips use an RTOS; that would just get in the way. The vision processing is done on the host, where you have heavy lifting capability with GPUs and tons of memory and so on. Doing that processing on the camera would quite expensive in terms of hardware and power, and wouldn't be able to adapt as well to new algorithms.

Animats 12y ago

Do not remove the Loyalty Bracelet. http://www.yuwanmei.com/products#4 http://www.yuwanmei.com/products#4

blinduck 12y ago
Wow, is this site an actual business or some kind of parody?
- Animats 12y ago
  That site is run by The Onion, which, for a few weeks, claimed to have been bought out by Yu Wan Mei Salvage Fisheries and Polymer Injection Corporation. Any time is Fish Time!

didgeoridoo 12y ago

Anyone else have trouble not automatically translating "LiPo" battery as "Lithium/Polonium" in their heads? That would be a bad battery.

minthd 12y ago

It seems like some components are missing, for example the gps and and microphone.

rasz_pl 12y ago

-failed to remove qrcode sticker from big chip? -failed to identify gyro/accelerometer/compass chips ifixit they are not, but its a good start