[FE training-materials-updates] kernel labs: "black" and "white" nunchuk clarification

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=14a4b625ba5092fcafb2dd68bcf135ee0b8d8664

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commit 14a4b625ba5092fcafb2dd68bcf135ee0b8d8664
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Sun Oct 20 08:10:32 2013 +0200

    kernel labs: "black" and "white" nunchuk clarification
    
    - Add details about the black and white nunchuks referred to
      by the nunchuk documentation.
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


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14a4b625ba5092fcafb2dd68bcf135ee0b8d8664
 .../kernel-i2c-communication.tex                   |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/labs/kernel-i2c-communication/kernel-i2c-communication.tex b/labs/kernel-i2c-communication/kernel-i2c-communication.tex
index 4838c45..399b14f 100644
--- a/labs/kernel-i2c-communication/kernel-i2c-communication.tex
+++ b/labs/kernel-i2c-communication/kernel-i2c-communication.tex
@@ -104,7 +104,16 @@ In the probe routine (run every time a matching device is found):
 
 \begin{enumerate}
 \item Using the I2C raw API (see the slides), send two bytes to the
-      device: \code{0xf0} and \code{0x55}. Make sure you check the return value of 
+      device: \code{0xf0} and \code{0x55}
+      \footnote{Your instructor supplied a white nunchuk to you, but you
+      can see that in
+      \url{http://web.engr.oregonstate.edu/~sullivae/ece375/pdf/nunchuk.pdf},
+      this initialization sequece corresponds to the so-called "black"
+      nunchuk. Apparently, the "black" and "white" models mentioned in
+      this document correspond to different versions originally sold
+      under the Nintendo brand. Our model is a generic implementation,
+      which apparently replicates the "black" one from Nintendo.}.
+      Make sure you check the return value of 
       the function you're using. This could reveal communication issues.
       Using LXR, find examples of how to handle failures properly using
       the same function.