Phytec nanoModul-164, Быстрый старт

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nanoMODUL-164 QuickStart Instructions
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PHYTEC Meßtechnik GmbH 2003 L-379e_4
The Keil tool chain collects all initialization information for pre-
initialized variables (e.g. int i=3;) during compile and link time. This
information is stored within a special segment in the form of a list of
binary data entries. To mark the end of this list, the tool chain adds a
special entry to the list. Whenever the startup code finds this special
entry it ends the initialization of variables and continues executing.
Note that this end of list entry comes from the start164.obj object file.
To ensure consideration of all of your pre-initialized variables, you
must move start164.obj to the end of the list of your link files.
Otherwise some of your pre-initialized variables may not be
initialized by the startup code during runtime. It is usually very
difficult to detect such a mistake.
We recommend to always move start164.a66 to the end of your
projects file list.
5.3 Linking and Locating
The Linker has to combine several re-locatable object modules
contained in object files and/or libraries to generate a single absolute
object.
In addition the Linker must locate several segments of type code,
constants and data to fixated address locations within the address
range of the microcontroller to ensure the natural or explicitly
declared properties of these segments.
Data segments must always be located to any kind of random access
memory (e.g. RAM), code and constants segments should be located
to any kind of non-volatile memory (e.g. Flash). The C166 family has
a Von-Neumann architecture which uses the same read signal to fetch
data and also code or constants. To distinguish between non-volatile
and modifiable memory physically different memory devices must be
addressable within different address ranges.