[FE training-materials-updates] Fix Nunchuk communication mode explanations

Michael Opdenacker michael.opdenacker at free-electrons.com
Wed Dec 4 15:43:37 CET 2013

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

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=ec016cf8b57259d1dd8a0f1568dc6ce43533dc2d


commit ec016cf8b57259d1dd8a0f1568dc6ce43533dc2d
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Wed Dec 4 15:37:38 2013 +0100

    Fix Nunchuk communication mode explanations
    - You don't write a value to a register. You just write bytes
      through I2C.
    - Apparently, the explanations we had before were for the wiimote,
      which has memory-mapped registers.
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


 .../kernel-i2c-communication.tex                   |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/labs/kernel-i2c-communication/kernel-i2c-communication.tex b/labs/kernel-i2c-communication/kernel-i2c-communication.tex
index 5950baf..6fb570a 100644
--- a/labs/kernel-i2c-communication/kernel-i2c-communication.tex
+++ b/labs/kernel-i2c-communication/kernel-i2c-communication.tex
@@ -106,12 +106,12 @@ In the probe routine (run every time a matching device is found):
 \item Using the I2C raw API (see the slides), send two bytes to the
       device: \code{0xf0} and \code{0x55}
       \footnote{There are two ways of communicating with a wiimote extension.
-        The first known way was with data encryption by writing the encryption
-        byte 0x00 to 0x40. With this way, you have to decrypt each bytes you
+        The first known way was with data encryption by writing two
+        bytes: 0x40 and 0x00. With this way, you have to decrypt each byte you
         read from the nunchuk (not so hard but something you have to do).
-        Unfortunately, using 0x00 as the encryption byte is not working on third
+        Unfortunately, such encryption doesn't work on third
         party nunchuks so you have to set up unencrypted communication by
-        writing 0x55 to 0xF0, then writing 0x00 to 0xFB. This is working across
+        writing 0xf0 and 0x55 instead. This works across
         all brands of nunchuks (including Nintendo ones).}.
       Make sure you check the return value of 
       the function you're using. This could reveal communication issues.

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