Pagination in CodeIgniter

Controller:
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public function index() {
        $count = $this->dcategory->Count_drugcategories();
        $page = ($this->uri->segment(2)) ? $this->uri->segment(2) : 0;
        $this->load->library('pagination');
        $config['base_url'] = base_url('drug_categories');
        $config['use_page_numbers'] = TRUE;
        $config['total_rows'] = $count;
        $config['per_page'] = 10;
        $config["uri_segment"] = 2;
        $this->pagination->initialize($config);
        $limit = $config['per_page'];
        $start = ($page  == 0) ? 0 : ($page * $config['per_page']) - $config['per_page'];
        $data['query'] = $this->dcategory->Getlist_drugcategories($start,$limit);      
        $seo['title'] = 'Drug Categories List | ekimed';
        $data['links'] = $this->pagination->create_links();
        $this->load->view('layout/header',$seo);
        $this->load->view('drug_categories/listdrugcategories',$data);
        $this->load->view('layout/footer');
    }

Model:
----------------------

function Getlist_drugcategories($limit=0,$start=0){
        $this->db->select('*');
        if($limit>0 && $start>=0) {
            $this->db->limit($limit,$start);
        } else {
            $this->db->limit(10);
        }
        $query = $this->db->get($this->drugs_category);
        if($query->num_rows() > 0){
            return $query->result();
        } 
        return FALSE;
    }

Views:
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<?php echo $links; ?>