Fix build warnings & errors

boards/beaglebone/ai/02-quick-start.rst

@@ -48,7 +48,11 @@ FAQ <https://git.beagleboard.org/beagleboard/beaglebone-ai/-/wikis/Frequently-As
    BeagleBone AI can run **HOT**! Even without running the accelerators,
    getting up to 70C is not uncommon.
 
-`Official BeagleBone Fan Cape <https://www.newark.com/element14/6100310/beaglebone-ai-fan-cape/dp/50AH3704>`_
+   Read about `Fan update for BeagleBone AI on Forum 
+   <https://forum.beagleboard.org/t/fan-update-for-beaglebone-ai/1964>`. 
+
+1. `Official BeagleBone Fan Cape <https://www.newark.com/element14/6100310/beaglebone-ai-fan-cape/dp/50AH3704>`_
+2. `Coolerguys 25mm (25x25x10) USB Fan <https://www.coolerguys.com/en-in/collections/usb-fans/products/25mm-25x25x10-usb-fan>`
 
 Main Connection Scenarios
 **************************

boards/beaglebone/ai/04-expansion.rst

@@ -964,13 +964,13 @@ In the table are the following notations:
 is activated by pulling the signal to GND.
 
 .. todo:: (Actually, on BeagleBone AI, I believe PWR_BUT is pulled to 3.3V,
-but activation is still done by pulling the signal to GND. Also, a quick
-grounding of PWR_BUT will trigger a system event where shutdown can
-occur, but there is no hardware power-off function like on BeagleBone
-Black via this signal. It does, however, act as a hardware power-on.)
+    but activation is still done by pulling the signal to GND. Also, a quick
+    grounding of PWR_BUT will trigger a system event where shutdown can
+    occur, but there is no hardware power-off function like on BeagleBone
+    Black via this signal. It does, however, act as a hardware power-on.)
 
 .. todo:: (On BeagleBone Black, SYS_RESET was a bi-directional signal, but
-it is only an output from BeagleBone AI to capes on BeagleBone AI.)
+    it is only an output from BeagleBone AI to capes on BeagleBone AI.)
 
 .. table:: P9.01-P9.05
 
@@ -1792,7 +1792,7 @@ Expansion Connector Headers
 ******************************
 
 .. todo:: discuss header options for working with the expansion connectors per 
-https://git.beagleboard.org/beagleboard/beaglebone-black/-/wikis/System-Reference-Manual#section-7-1
+    https://git.beagleboard.org/beagleboard/beaglebone-black/-/wikis/System-Reference-Manual#section-7-1
 
 Signal Usage
 ****************

books/pru-cookbook/01case/case.rst

@@ -582,11 +582,15 @@ Now run a program on another computer that generated E1.31 packets.
 
 .. _case_e1.31_example:
 
-.. literalinclude:: ../code/02start/e1.31-test.py
+Controlling NeoPixels
+---------------------
+
+.. literalinclude:: ../code/01case/e1.31-test.py
    :caption: e1.31-test.py -Example of generating packets to control the NeoPixels
+   :language: python
    :linenos:
 
-:download:`e1.31-test.py <../code/02start/e1.31-test.py>`
+:download:`e1.31-test.py <../code/01case/e1.31-test.py>`
 
 .. todo:: document the code
 

books/pru-cookbook/02start/start.rst

@@ -330,7 +330,7 @@ Solution
 The 'hello, world' of the embedded world is to flash an LED. :ref:`start_hello` 
 is some code that blinks the ``USR3`` LED ten times using the PRU.
 
-.. todo:: The *'s and _'s in the code are messing with the formatting.
+.. todo:: The 's and _'s in the code are messing with the formatting.
 
 .. _start_hello: