diff --git a/README.md b/README.md
index e9dda35..fd3944c 100644
--- a/README.md
+++ b/README.md
@@ -38,11 +38,11 @@ The keybrd_DH emulates the DataHand keyboard.
 It has 72 keys, 4 layers, a sub-layer, 2 matrices, and many features.
 The keybrd_DH and its instantiation files contain about 800 lines of code.
 
-   [mainSketch.ino](https://github.com/wolfv6/keybrd_DH/blob/master/examples/keybrd_DH/mainSketch.cpp)<br>
-   [instantiations_ports.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_ports.h)<br>
-   [instantiations_LEDs.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_LEDs.h)<br>
-   [instantiations_codes.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_codes.h)<br>
-   [instantiations_matrix.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_matrix.h)
+[mainSketch.ino](https://github.com/wolfv6/keybrd_DH/blob/master/examples/keybrd_DH/mainSketch.cpp)<br>
+[instantiations_ports.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_ports.h)<br>
+[instantiations_LEDs.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_LEDs.h)<br>
+[instantiations_codes.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_codes.h)<br>
+[instantiations_matrix.h](https://github.com/wolfv6/keybrd_DH/blob/master/src/instantiations_matrix.h)
 
 Support
 -------
diff --git a/doc/keybrd_library_user_guide.md b/doc/keybrd_library_user_guide.md
index f5afd38..5a5b18f 100644
--- a/doc/keybrd_library_user_guide.md
+++ b/doc/keybrd_library_user_guide.md
@@ -65,18 +65,19 @@ For Linux:
 4. Launch Arduino IDE from /opt/arduino-1.x.x/arduino
 
 ### Download and unpack keybrd-master.zip into your Arduino directory
-<--! todo update after testing Arduino library manager
+<!-- todo update after testing Arduino library manager
 link from tutorial 7 ## Publishing
     https://www.arduino.cc/en/Guide/Libraries
      * Installing Additional Arduino Libraries
      * Using the Library Manager
  -->
+
 Down load keybrd-master.zip from the [Download ZIP](https://github.com/wolfv6/keybrd) button.
 
 Unpack keybrd-master.zip into your Arduino directory on your system (default location is ~/Documents/Arduino/).
 
 ### keybrd library and keybrd extension libraries
-<--! todo update after testing Arduino library manager -->
+<!-- todo update after testing Arduino library manager -->
 
 The keybrd library contains the foundation classes for creating a keyboard firmware.
 For emphasis, it is referred to as the "core keybrd library".
@@ -146,7 +147,7 @@ The first two fields are mandatory, the remaining fields are optional.
 The physical martix rows and columns on a keyboard can be in any direction or shape.
 [diode](https://en.wikipedia.org/wiki/Diode) orientation is specified in [Matrix.h](https://github.com/wolfv6/keybrd/blob/master/src/Matrix.h)
 
-[Diode](https://github.com/wolfv6/keybrd/blob/master/tutorials/images/120px-Diode_pinout_en_fr.svg.png)
+![Diode](https://github.com/wolfv6/keybrd/blob/master/tutorials/images/120px-Diode_pinout_en_fr.svg.png)
 
 Diagram is of typical through-the-hole diode in same alignment as diode symbol.
 Cross bar and band depict the cathode.
@@ -186,6 +187,7 @@ Hardware items to check:
 * Diode orientation
 * 5 volts across power and ground
 * To validate keyboard hardware, modify the simple single-layer keybrd sketch from the tutorial.
+
 <!-- todo after teensy LC bb, linke to minimal keybrd sketch
 [minimal keybrd sketch](blob/master/tutorials/keybrd_2_single-layer_annotated/keybrd_2_single-layer_annotated.ino).
  -->