cordova-plugin-ble (evothings) WriteCharacteristics problems

Question

I'm using cordova-plugin-ble of evothing and I can't send data to my device( HM10). I´m trying to send to bluetooth device a string ('a') but not working.

I have tried with these options also:

 1. 'a' letter en hexa 
var data = '61';
 2. whit array
var data = new Unit8Array(2);
        data[0] = '6';
        data[2] = '1'; 
3. var data = new Unit8Array();
        data[0] = 'a';

4. var data = new Unit8Array();
        data[0] = '61';

Answer 1

I got it guys!. I was sending the information wrong, I found this function and implemented it in my code:

str2ab: function (str){
          var buf = new ArrayBuffer(str.length * 2); // 2 bytes for each char
          var bufView = new Uint16Array(buf);
          for (var i = 0, strLen = str.length; i < strLen; i++) {
            bufView[i] = str.charCodeAt(i);

          return bufView;  
        }
    }