parseType = function(buffer) {
    var result = '';
    result += String.fromCharCode(buffer[0]);
    result += String.fromCharCode(buffer[1]);
    result += String.fromCharCode(buffer[2]);
    result += String.fromCharCode(buffer[3]);
    return result;
  }
Returns the string representation of an ASCII encoded four byte buffer.
@param buffer {Uint8Array} a four-byte buffer to translate
@return {string} the corresponding string