64bit double float to byteArray ?

Hi there,

I've started developing a widget to remote control via BLE the Insta360 One R action camera.

https://apps.garmin.com/us-US/apps/bb53f4bb-6c8c-4369-bca9-84cc09b25526

I've already implement basic remote control functionality and now I'm in the phase of sending GPS Telemetry to the camera.

However the camera only wants 64bit double float GPS coordinates , speed, altitude, etc, values sent in HEX format that I handle through byteArrays, but the encodeNumber method only supports 32bit encoding.

Is there a way around this ?

Thanks for your help.

Greg

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9635560 over 4 years ago in reply to ars.fabula +1

I must have had a slow day yesterday!

I went a different route based on Jim's link:

ETA: I HAD A PROBLEM WITH NEGATIVE VALUES! I've edited the above to fix it.

ETA2: I ALSO HAD A PROBLEM WITH FRACTIONAL…

9635560 over 4 years ago in reply to 9635560 +1

And somewhat unnecessarily, going the other way:

function flBytesToType(bytes,exponentNumBits,storeBits,input) {
    	// 0. Set some constant values
    	var bias = (1 << (exponentNumBits-1)) - 1, numBytes…

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stan 2 months ago

I have implemented a library for converting doubles to byte arrays in https://github.com/mannyray/GarminBytePacking which adds the encoding to doubles

var someLong = 123l;
var byteArray = BytePacking.BPLong.longToByteArray(someLong);
Test.assert(byteArray.equals([0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x7B]b));
Test.assert(BytePacking.BPLong.byteArrayToLong(byteArray) == someLong);

var someFloat = 123.34f;
byteArray = BytePacking.BPFloat.floatToByteArray(someFloat);
Test.assert(byteArray.equals([0x42,0xF6,0xAE,0x14]b));
Test.assert(BytePacking.BPFloat.byteArrayToFloat(byteArray) == someFloat);

var someDouble = 1234578.65432d;
byteArray = BytePacking.BPDouble.doubleToByteArray(someDouble);
Test.assert(byteArray.equals([0x41,0x32,0xD6,0x92,0xA7,0x81,0x83,0xF9]b));
Test.assert(BytePacking.BPDouble.byteArrayToDouble(byteArray) == someDouble);