diff --git a/README.md b/README.md
index 8ba1239..3a872b9 100644
--- a/README.md
+++ b/README.md
@@ -31,6 +31,8 @@ It runs the breadboard keyboard in this picture.
+
+
Example complex keybrd sketch
-----------------------------
keybrd_DH and its instantiation files contain about 800 lines of code.
diff --git a/tutorials/tutorial_10_writing_your_own_port_classes.md b/tutorials/tutorial_10_writing_IOE_Port_classes.md
similarity index 85%
rename from tutorials/tutorial_10_writing_your_own_port_classes.md
rename to tutorials/tutorial_10_writing_IOE_Port_classes.md
index 6a1adea..1c34dfc 100644
--- a/tutorials/tutorial_10_writing_your_own_port_classes.md
+++ b/tutorials/tutorial_10_writing_IOE_Port_classes.md
@@ -1,13 +1,13 @@
-Tutorial 10 - writing your own port classes
+Tutorial 10 - writing IOE Port classes
===========================================
Port classes are the keybrd library's interface to I/O expander ports.
-To write your own port classes:
+To write your own Port class:
-1. Get a copy of the controller or I/O expander datasheet.
+1. Get a copy of the I/O expander datasheet.
2. Study other keybrd Port classes.
-For example, the keybrd_DH library use these keybrd classes for its PCA9655E I/O:
+For example, the keybrd_DH library uses these keybrd classes for its PCA9655E I/O expander:
* PortWrite_PCA9655E
* PortRead_PCA9655E
* LED_PCA9655E
diff --git a/tutorials/tutorial_3b_autoShift.md b/tutorials/tutorial_3b_autoShift.md
index c4b36aa..afe9c8a 100644
--- a/tutorials/tutorial_3b_autoShift.md
+++ b/tutorials/tutorial_3b_autoShift.md
@@ -23,7 +23,7 @@ Exercises
| Layout | **0** | **1** |
|:------:|:-----:|:-----:|
| **0** | a ! 6 | b @ 7 |
-| **1** | sym |. num .|
+| **1** | sym | num |
keybrd tutorial by Wolfram Volpi is licensed under a Creative Commons Attribution 4.0 International License.
Permissions beyond the scope of this license may be available at https://github.com/wolfv6/keybrd/issues/new.