function transfer(address _to, uint _value) onlyWhenTokenIsOn onlyPayloadSize(2 * 32) public returns (bool success){
        
        require(
            balances[msg.sender]>=_value 
            && _value > 0
            && now > blockedTill[msg.sender]
        );
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        emit Transfer(msg.sender,_to,_value);
        return true;
    }