请问谁知道怎么用CI调用存储过程?

<?php
require_once('nusoap.php');
function addpoint($AccountID,$PointNum,$LastAddPointTime)
{
    $conn = mssql_connect("localhost", "liujun", "123456") or die("无法连接到数据库");
    mssql_select_db("demo", $conn) or die("选择数据库失败!");

  $stmt = mssql_init("baseinfo_addpoint", $conn) or die("初始化存储过程失败!");
    mssql_bind($stmt, "@AccountID", $AccountID, SQLINT4);
    mssql_bind($stmt, "@PointNum", $PointNum, SQLINT4);
    mssql_bind($stmt, "@LastAddPointTime", $LastAddPointTime, SQLVARCHAR);
        $rs = mssql_execute($stmt, false);
}

$soap = new soap_server;
$soap->register('addpoint');
$soap->service($HTTP_RAW_POST_DATA);
   
?>

这段准备改CI来写，CI里面有没有相关的函数？