diff --git a/codeboot.bundle.js b/codeboot.bundle.js
index fb8baa86..2455e9d9 100644
--- a/codeboot.bundle.js
+++ b/codeboot.bundle.js
@@ -33128,7 +33128,7 @@ function CodeBoot() {
 
     var cb = this;
 
-    cb.version = '3.1.8';
+    cb.version = '3.1.10';
 
     cb.cmds = null;
     cb.cmds_valid = false;
@@ -37452,14 +37452,12 @@ DrawingWindow.prototype.set_thickness = function (width) {
 
 DrawingWindow.prototype.pu = function () {
     var dw = this;
-    dw.pen_height++;
+    dw.pen_height = 1;
 };
 
 DrawingWindow.prototype.pd = function () {
-    var dw = this;
-    if (--dw.pen_height <= 0) {
-        dw.pen_height = 0;
-    }
+  var dw = this;
+  dw.pen_height = 0;
 };
 
 DrawingWindow.prototype.triangle = function (h, base) {
diff --git a/include/codeboot.js b/include/codeboot.js
index d91d722b..aeb7adf3 100644
--- a/include/codeboot.js
+++ b/include/codeboot.js
@@ -4,7 +4,7 @@ function CodeBoot() {
 
     var cb = this;
 
-    cb.version = '3.1.9';
+    cb.version = '3.1.10';
 
     cb.cmds = null;
     cb.cmds_valid = false;
diff --git a/include/drawing.js b/include/drawing.js
index 4d0977c0..0964dd4a 100644
--- a/include/drawing.js
+++ b/include/drawing.js
@@ -272,14 +272,12 @@ DrawingWindow.prototype.set_thickness = function (width) {
 
 DrawingWindow.prototype.pu = function () {
     var dw = this;
-    dw.pen_height++;
+    dw.pen_height = 1;
 };
 
 DrawingWindow.prototype.pd = function () {
-    var dw = this;
-    if (--dw.pen_height <= 0) {
-        dw.pen_height = 0;
-    }
+  var dw = this;
+  dw.pen_height = 0;
 };
 
 DrawingWindow.prototype.triangle = function (h, base) {