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Also for others who may stumble upon this...I found out after reading the datasheets of the accelerometer and digging into the Espruino code for acceleration on the puck and it seems to be that the Puck's accelerometer is being put into low-power consumption mode which has a max polling rate of only 52Hz, but by doing the following two lines after Puck.accelOn(interval):

    Puck.accelOn(1660);
    Puck.accelWr('0x15', '0x00');
    Puck.accelWr('0x16', '0x00');

It should put the accelerometer chip into "high-performance operating mode enabled" which can allow up to 6.66kHz, but the max the puck can handle (based on documentation) is 1.66Hz. Note that battery consumption will be more, however.

I believe this happens here in the Espruino code: https://github.com/espruino/Espruino/blob/3fbcd63bc327de67c88bf19efd9e4776249ebd3e/libs/puckjs/jswrap_puck.c#L528-L542

Thanks for your input! Yes, I think I may try Bluetooth.write thru UART and not use NRF.updateServices as well as combining all the values into one packet which should give me a lot more than what I am getting currently.

Hi Gordon, thanks a lot for your reply. I will try it out. Much appreciated

Sorry I forgot to attach my code for reference. Please find below.

var accelOn = false;
var batteryLevel = Puck.getBatteryPercentage();
  
NRF.nfcURL("Puck.js 9e03");

setWatch(function() {
  if (accelOn) {
    Puck.accelOff();
    accelOn = false;
    NRF.nfcRaw(new Uint8Array([193, 1, 0, 0, 0, 13, 85, 3, 80, 117, 99, 107, 46, 106, 115, 32, 57, 101, 48, 51]));
    batteryLevel = Puck.getBatteryPercentage();
  } else {
    Puck.accelOn(1660);
    accelOn = true;
  }
}, BTN, {edge:"rising", repeat:1, debounce:20});


NRF.setServices({
  0x2713: {
    "e482a929-e02a-4e8a-8296-cca819ebe0c6": {
      value: String(Puck.getTemperature()),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Accelerometer X",  // optional, default is null,
    },
    "cad35f0b-8a1a-442c-b249-4698e582fcf4": {
      value: String(Puck.getTemperature()),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Accelerometer Y",  // optional, default is null,
    }, 
    "4249a4c7-9a03-428d-818a-24a7c5aefb4a": {
      value: String(Puck.getTemperature()),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Accelerometer Z",  // optional, default is null,
    },
    "54e832b7-714e-4aa5-ada9-e21dd2006844": {
      value: String(Puck.getTemperature()),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Gyroscope X",  // optional, default is null,
    },
    "cbbb698d-878e-473a-9625-fbe0243ac8e1": {
      value: String(Puck.getTemperature()),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Gyroscope Y",  // optional, default is null,
    }, 
    "6db27825-05fa-4984-9fed-568edd9f1fe8": {
      value: String(Puck.getTemperature()),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Gyroscope Z",  // optional, default is null,
    },
    "1bdf76b4-006a-4e20-8a09-fb87b8f4b29d": {
      value: String(batteryLevel),
      maxLen: 20,
      broadcast: true, // optional, default is false
      readable: true,   // optional, default is false
      writable: false,   // optional, default is false
      notify: true,   // optional, default is false
      indicate: true,   // optional, default is false
      description: "Battery Level",  // optional, default is null,
    }
  }
});

NRF.setAdvertising({
  0x2713: undefined
});

Puck.on('accel', function(a) {
  NRF.updateServices({
    0x2713: {
      "e482a929-e02a-4e8a-8296-cca819ebe0c6": {
        value: String(a.acc.x),
        notify: true,
        readable: true
      },
      "cad35f0b-8a1a-442c-b249-4698e582fcf4": {
        value: String(a.acc.y),
        notify: true,
        readable: true
      },
      "4249a4c7-9a03-428d-818a-24a7c5aefb4a": {
        value: String(a.acc.z),
        notify: true,
        readable: true
      },
      "54e832b7-714e-4aa5-ada9-e21dd2006844": {
        value: String(a.gyro.x),
        notify: true,
        readable: true
      },
      "cbbb698d-878e-473a-9625-fbe0243ac8e1": {
        value: String(a.gyro.y),
        notify: true,
        readable: true
      },
      "6db27825-05fa-4984-9fed-568edd9f1fe8": {
        value: String(a.gyro.z),
        notify: true,
        readable: true
      },
      "1bdf76b4-006a-4e20-8a09-fb87b8f4b29d": {
        value: String(batteryLevel),
        notify: true,
        readable: true
      }
    }
  });
});

Hello,

I was trying to use a Puck.js v2.1 to broadcast accelerometer and gyro data to a mobile phone app at around 1kHz, but I can only get 50Hz. I am trying to double-integrate acceleration to get the world-frame to pose (position and orientation). I tried setting this function to 6600Puck.accelOn(6600); which matched one of the data rates supported by the accelerometer, but it still was around 45-50Hz which is not desired. How can I either increase the data rate through Javascript OR modify the existing firmware C code and reflash the Puck.js? If I want to modify the existing firmware what are the steps to do this? I believe the code base is here? https://github.com/espruino/Espruino. How would building binaries/installing the code work?

Hello there.