Javascript计时器问题

Question

我正在从db获取的动态数据数组上设置一个计时器。它可以正常工作但是当我第二次单击该按钮时，它会非常快速地增加秒数。我还想在每次单击按钮时将初始计数设置回60。有人可以帮忙吗？到目前为止，我的代码如下：

<script>
  var counts = [];
  var xs = [];
  for (var i = 1; i < 61; i++) {
        counts.push(61);
        xs.push(0);
    };


    function timer(id) {           
        xs[id] = setTimeout("timer(" + id + ")", 1000);
        counts[id] = counts[id] - 1;
        if (counts[id] < 1) { counts[id] = 0; }
        document.getElementById("but" + id).innerHTML = counts[id];

    }

           function restarttimer(id) {           
        xs[id] = setTimeout("timer(" + id + ")", 1000);
        counts[id] = counts[id] - 1;
        if (counts[id] < 1) { counts[id] = 0; }
        document.getElementById("but" + id).value = counts[id];

    }


</script>


<?php

$i=1;
?>
<table id="itemTable"><tr>
  <?php
while($r=mysql_fetch_array($resultSearch))
{
    ?>


<td>

    <p id="but<?php echo $r['itemID'];?>">>
    </p>

      <input type="button" value="bid" onclick="timer(<?php echo $r['itemID'];?>)" />



  </td>
<?php
    if($i % 3 == 0)
            echo '</tr><tr>';
   $i++;
}

＆GT？;