diff --git a/printlib.php b/printlib.php
index 745458c..d20e721 100644
--- a/printlib.php
+++ b/printlib.php
@@ -93,7 +93,7 @@ function printean8($data) {
 function rawdlen($data) {
     $len = strlen($data);
     $l = ($len + 3) % 256;
-    $h = intdiv($len / 256);
+    $h = intdiv($len, 256);
     if ($l<16) {
             $l=hex2bin("0" . dechex($l));
         } else {
@@ -106,7 +106,7 @@ function rawdlen($data) {
         }
     return $l . $h;
 }
-function printqr($data, $size) {
+function printqr($data, $size = 16) {
     if (strlen($data)<7088) {
         if ($size<16) {
             $encs=hex2bin("0" . dechex($size));