Base files

1 files changed, 34 insertions, 0 deletions

diff --git a/doc/bsp_howto/target.t b/doc/bsp_howto/target.t
new file mode 100644
index 0000000000..5248390cf0
--- /dev/null
+++ b/doc/bsp_howto/target.t
@@ -0,0 +1,34 @@
+@chapter = Target Dependent and Board Dependent Files
+
+RTEMS divides board dependencies into two parts :
+
+@itemize @bullet
+
+@item the CPU dependant code : it provides basics calls to the kernel,
+just as the context switch or the interrupt subroutine implementations.
+Sources for the supported families of processors can be found in
+$RTEMS_ROOT/c/src/exec/score/cpu. A good starti ng point for a new family
+of processors is the no_cpu directory, which holds both prototypes and
+descriptions of each needed CPU dependant function. 
+
+@item the board dependant code : it includes support for a given board,
+such as the board initialization code and drivers for the various devices:
+clock, UARTs, ethernet board, etc.
+
+
+@end itemize
+
+Porting RTEMS on a new board should raise two questions :
+
+@itemize @bullet
+
+@item is the main board CPU supported ?
+
+@item does a BSP for a similar board exists ?
+
+@end itemize
+
+If the main board CPU is supported, you will only have do write the Board
+Support Package. Otherwise you'll have to write both CPU dependant code
+and the BSP. One should always start writing a BSP from a similar one. 
+