Espruino on your watch!

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  • The new tracker arrived today! It is a Nordic one and looks identical to the one @Gordon posted.

    It's really weird: Seeing them together shows that they are extremely similar, yet different.

    I posted some pictures showing the differences:­2838015526260741­2837420060921856­2836483376414726

    The Nordic chip variant feels to be higher quality - the band is softer and more flexible and the screen is much sharper and it updates much more quickly.

    There are smaller differences - one has an oval shaped button, and the other a rectangular one. The battery clips are an almost identical design but yet made of a slightly different quality of plastic.

    The Nordic based one advertises itself as "YDY_P102" to Bluetooth and the other one seems to have decided not to advertise any more....

    What to do with it? I figure it would work strapped to a bicycle wheel as a cycle computer, or could make some kind of shoe-mounted device to communicate online by morse code - pub-quiz cheat-tastic!

  • Is there any differences we can tell from the listings apart from that one saying it has the NRF chip which I guess is a big enough clue.

    Even thought my current model isn't the Nordic chip I realized, had it been I wouldn't of known how to flash it anyway. How is it you're doing that?

  • You have to connect to the GND, DIA and CLK pads, then you can use a 'normal' SWD programmer. Any STM32Discovery kit will work, and then you can use this script with OpenOCD

  • @Gordon I'm looking at trying to build my own watch using an nrf51822 module ( this one in particular).

    I got the Microbit firmware onto an nrf51822 board that I've got using your script and managed to get my phone connected via web Bluetooth (no luck on Windows or ubuntu). From what I can tell, most software "pairs" with a Bluetooth device before firing up comms, but it looks like this uses an unsecured serial interface. Do you have any plans to expand on the Bluetooth capabilities for Espruino on this chip? The smartwatch app I'd like to use with it seems to require pairing in order to open up a serial port.

  • web Bluetooth (no luck on Windows or ubuntu).

    You could use EspruinoTools to get a command-line interface if that helps - it uses the bleat NPM module which has some support for other OS's.

    From what I can tell, most software "pairs" with a Bluetooth device before firing up comms

    This definitely does establish some kind of connection - there's no pairing though. It's something that could be added (I think relatively easily) but it's not a priority at the moment.

    Are you sure you're not getting BTLE confused with 'normal' bluetooth? The chip's BTLE won't establish a 'normal' serial port connection on your phone - you need some special code from Nordic for the 'Nordic UART', so an existing smartwatch app is unlikely to work unless it has specific support for that.

  • I'll give EspruinoTools a go, that sounds better.

    The connection issues probably are the Nordic specific thing. I thought there was a generic serial profile for ble and assumed it was being used. Thanks!

  • Yeah, as far as I know there's no BLE profile for UARTs (which seems insane, but hey). The Nordic one is about as near a standard as you're going to get for now I think.

  • This is great, thank you :)
    I will try to get the firmware before flashing your code do you have any other suggestions before I mess original? Do you maybe got some updates with code :)

  • I haven't done anything with it for a while I'm afraid.

    I'd strongly suggest buying an nRF51 devkit though - it'll make it much easier to flash the firmware onto the watch (and to read the original firmware first, so you can restore it later if you want to!).

  • tnx,
    I will try to get it working and put it on my blog.
    I see now that maybe I could use arduino, I will try that to...­rduino

  • hmm, a big fail for now :)
    but here it is on my blog I have learned a lot but failed to get firmware­acelet-wristband/

  • @user67183 Not sure if it's just me, but some of your Inline Images don't work.

  • tnx I will fix it now

  • is it better now?

  • Ah yes, fixed.

  • I have successfully wake up the bracelet after removing battery, and this night I was able to get all data out, but now there is a question. Is this firmware or some rubbish inside file.
    file is here:

  • This bracelet looks interesting. It's got a heart rate monitor and advertises "CPU: nRF51822" in the description, I meant I don't trust it, but Imma try it anyway, it also has a much better strap. I'll post results when it arrives.

  • Keep us posted on how you get on - it would brilliant if espurino and Bluetooth work on that!

  • Of course :p Estimated delivery of 14-30th Sept, gonna be the longest 18-34 days ever. Really gonna suck if it isn't even an nRF51 chip :/
    Even if it is you gotta remember there isn't much room on that chip, nothing too complex will fit :(

  • Here are pictures of setting arduino

    I even put 32k oscilator, but still does not vibrate
    I now see that I did not solder one capacitor well so I maybe that is a reason ...

  • And if we get it to work with arduino it will be lots of space for play
    (8%) of program storage space. Maximum is 65,536 bytes

  • got the LED working on TX pin
    TX pad P0.18
    this is arduino pin D9 ;)

    I will now try to check if I name it as some other pin like D18 ...

  • Glad you got the Arduino IDE going - shame about the troubles with Espruino... I think the problem with some of these devices is the board layout changes a lot between revisions, so there's no guarantee that the display/etc are in the same place..

    @Ducky - that one looks very cool. Seems similar to mine but with a heart rate monitor on it, which would be really fun to play with... Hope you have some luck with it!

  • @Gordon - I now got new version of arduino where all could work got it today so I need to try.
    I have tested and there I can get
    UART TX on tx and rx pins (couse I broke TX pin :))
    i2c scanner (fixed version for NRF51) - returns address of accelerometer
    and garbage on screen with oled - I use 64x48 library im in contact with developer and having problen I got only garbage on screen

    maybe you can use some mbed code I can share it so you can get all of this on espruino?

  • @Gordon Thanks, I sent the ebay seller a message asking if he could confirm that it is in-fact an nRF51, they said it is. Now just to wait, oh and to find my SWD Programmer :p

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Espruino on your watch!

Posted by Avatar for Gordon @Gordon