Connect to custom table works fine but don't know how to get pagination to work?

<?php
// Connects to your Database
mysql_connect("localhost", "user", "password") or die(mysql_error());
mysql_select_db("modx") or die(mysql_error());

//This checks to see if there is a page number. If not, it will set it to page 1
if (!(isset($pagenum)))
{
$pagenum = 1;
}

//Here we count the number of results
//Edit $data to be your query
$data = mysql_query("SELECT * FROM tblprojects") or die(mysql_error());
$rows = mysql_num_rows($data);

//This is the number of results displayed per page
$page_rows = 5;

//This tells us the page number of our last page
$last = ceil($rows/$page_rows);

//this makes sure the page number isn't below one, or more than our maximum pages
if ($pagenum < 1)
{
$pagenum = 1;
}
elseif ($pagenum > $last)
{
$pagenum = $last;
}

//This sets the range to display in our query
$max = 'limit ' .($pagenum - 1) * $page_rows .',' .$page_rows; 

//This is your query again, the same one... the only difference is we add $max into it
$data_p = mysql_query("SELECT * FROM tblprojects $max") or die(mysql_error());

//This is where you display your query results
while($info = mysql_fetch_array( $data_p ))
{
Print $info['Grant_Award'];
echo "<br>";
Print $info['Project_Ref'];
echo "<br>";
Print $info['LA_Area'];
echo "<br>";
Print $info['the_url'];
echo "<p>";
}
echo "<p>";

// This shows the user what page they are on, and the total number of pages
echo " --Page $pagenum of $last-- <p>";

// First we check if we are on page one. If we are then we don't need a link to the previous page or the first page so we do nothing. If we aren't then we generate links to the first page, and to the previous page.
if ($pagenum == 1)
{
}
else
{
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=1'> <<-First</a> ";
echo " ";
$previous = $pagenum-1;
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=$previous'> <-Previous</a> ";
}

//just a spacer
echo " ---- ";

//This does the same as above, only checking if we are on the last page, and then generating the Next and Last links
if ($pagenum == $last)
{
}
else {
$next = $pagenum+1;
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=$next'>Next -></a> ";
echo " ";
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=$last'>Last ->></a> ";
}
?> 

<?php

//This checks to see if there is a page number. If not, it will set it to page 1

$pagenum = isset($_GET['pagenum'])?$_GET['pagenum']:1;

//Here we count the number of results
//Edit $data to be your query
$data = $modx->db->query("SELECT * FROM tblprojects");
$rows = $modx->db->getRecordCount($data);

//This is the number of results displayed per page
$page_rows = 5;

//This tells us the page number of our last page
$last = ceil($rows/$page_rows);

//this makes sure the page number isn't below one, or more than our maximum pages
if ($pagenum < 1)
{
$pagenum = 1;
}
elseif ($pagenum > $last)
{
$pagenum = $last;
}

//This sets the range to display in our query
$max = 'limit ' .($pagenum - 1) * $page_rows .',' .$page_rows; 

//This is your query again, the same one... the only difference is we add $max into it
$data_p = $modx->db->query("SELECT * FROM tblprojects $max");

//This is where you display your query results
while($info = $modx->db->getRow( $data_p ))
{
Print $info['Grant_Award'];
echo "<br>";
Print $info['Project_Ref'];
echo "<br>";
Print $info['LA_Area'];
echo "<br>";
Print $info['the_url'];
echo "<p>";
}
echo "<p>";

// This shows the user what page they are on, and the total number of pages
echo " --Page $pagenum of $last-- <p>";

// First we check if we are on page one. If we are then we don't need a link to the previous page or the first page so we do nothing. If we aren't then we generate links to the first page, and to the previous page.
if ($pagenum == 1)
{
}
else
{
echo ' <a href="[~[*id*]~]&pagenum=1"> <<-First</a> ';
echo " ";
$previous = $pagenum-1;
echo ' <a href="[~[*id*]~]&pagenum='.$previous.'"> <-Previous</a> ';
}

//just a spacer
echo " ---- ";

//This does the same as above, only checking if we are on the last page, and then generating the Next and Last links
if ($pagenum == $last)
{
}
else {
$next = $pagenum+1;
echo ' <a href="[~[*id*]~]&pagenum='.$next.'"> >Next -></a> ';
echo " ";
echo ' <a href="[~[*id*]~]&pagenum='.$last.'"> >Last ->></a> ';
}
?> 

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