puckjs bleak python mac / read advertisements

[espruino-discuss]

Posted at 2024-03-07 by user155285

Hello,
is annoying out there managed to read accelerometer datas of the puckjs thru advertisement (manufacturer data) using the bleak python library?
I tried all the different tutorial on the subject but not luck :/

[espruino-discuss]

Posted at 2024-03-08 by @gfwilliams

Try using the Espruino code from https://www.espruino.com/BLE+Advertising#python

And then use:

#!python3
# Scans for and outputs BLE advertising containing manufacturer data 0x0590
# needs: `pip install bleak`
import asyncio
import array
from bleak import BleakScanner
from bleak import BleakClient

async def main():
    stop_event = asyncio.Event()
    
    def callback(device, advertising_data):
        # print(advertising_data)  # debug
        if advertising_data.manufacturer_data and (0x0590 in advertising_data.manufacturer_data):  
          d = advertising_data.manufacturer_data[0x0590]          
          print("Found Espruino Manufacturer data", device)
          if advertising_data.local_name:
            print("  Name: ", advertising_data.local_name);
          print("  Data: ", ", ".join(hex(b) for b in d))
          # You could call stop_event.set() here if you found the device you want
          # and scanning will be stopped
        pass

    async with BleakScanner(callback) as scanner:
        await stop_event.wait()
       
# Start scanning       
asyncio.run(main())

(I'll update the above link with the Bleak example - previously it only included code for Python Bluepy).

It should be pretty straightforward to modify it to output accelerometer data, but let me know if you have any issues

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Posted at 2024-03-08 by user155285

Thanks @gfwilliams, works great!
what would be the best way to advertise more frequently ? ( the fastest we can)

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Posted at 2024-03-08 by @gfwilliams

Just use NRF.setAdvertising(..., {interval:20}) on the Puck - 20ms is the fastest I think (50 times/sec)

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Posted at 2024-03-08 by user155285

I did:
NRF.setTxPower(4);
NRF.setConnectionInterval(20);
NRF.setAdvertising({}, { manufacturer: 0x0590, manufacturerData: [pushbuttonCounter] },{interval:20});

but still get the same result (or actually a tiny slower). I get a burst of 5 lines printed every second or so. Would I need to change something on the bleak side?

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Posted at 2024-03-11 by @gfwilliams

You need:

NRF.setAdvertising({}, { manufacturer: 0x0590, manufacturerData: [pushbuttonCounter], interval:20});

It's meant to go in the second argument, not the third - then hopefully things will work better

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Posted at 2024-03-11 by @fanoush

but still get the same result

and BTW, if you expect the [pushbuttonCounter] to magically update the advertising data automatically when it changes then it won't do that

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Posted at 2024-03-11 by user155285

Thanks!
got it working, as blemidi on osx is broken in term of auto reconnection I am basically making a workaround with advertisements. I am using the motion example, is there a way to advertise at interval 20 but only when the device is moving?

here is the code:

NRF.setTxPower(4);
//NRF.setConnectionInterval(20);

function rescaleToMidiCC(value, oldMin, oldMax) {
  var newMin = 0;
  var newMax = 127;
  var rescaled = Math.round((value - oldMin) * (newMax - newMin) / (oldMax - oldMin) + newMin);
  rescaled = Math.min(127, Math.max(0, rescaled));
  return rescaled;
}


require("puckjsv2-accel-movement").on();
var idleTimeout;

Puck.on('accel',function(a) {
  LED.set();

  if (idleTimeout) clearTimeout(idleTimeout);
  idleTimeout = setTimeout(function() {
    idleTimeout = undefined;
    LED.reset();
    //active = false ;
  },500);
  const accel = Puck.accel();
  var x = ((accel.acc.x/128000)*10) *127;
  var y = ((accel.acc.y/128000)*10) *127;
  x = rescaleToMidiCC(x, -120, 120);
  y = rescaleToMidiCC(y, -120, 120);
  print(x + " " + y);
  NRF.setAdvertising({}, { manufacturer: 0x0590, manufacturerData:           [x,y], interval:20});

});

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Posted at 2024-03-13 by @gfwilliams

Yes - looks like you're using require("puckjsv2-accel-bigmovement") anyway and even have the idle timeout, so all you need is:

NRF.setAdvertising({}, { manufacturer: 0x0590, manufacturerData: [x,y], interval:375});

inside your idleTimeout = setTimeout(function() { function