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raspberrypi/boards/pi2/SVC_BOOT/uart02/README

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See the top level README for information on where to find documentation
for the raspberry pi and the ARM processor inside. Also find information
on how to load and run these programs.
This example is for the pi2, see other directories for other flavors
of raspberry pi.
This example requires a config.txt along with a kernel7.img.
This example isolates the four cores into separate execution paths.
Core zero moves forward and sets things up. The other three sit and
poll a memory location, when the value in that memory location changes
from zero to something else they branch to that address assuming it
is their entry point.
This example has each core print something out the uart based on a
timer. Generally not a good idea to do it this way, you normally want
the shared resource properly shared. At the same time this is
properly shared in that the timer is insuring each core touches the
uart at a different time, and space out enough to not cause problems.
The output should be
0123
0123
0123
0123
repeated forever, core 0 prints out 0 and cr/lf, core 1 prints the 1
core 2 the 2 and core 3 the 3.