Zilog Z8F0130 - Manual (Page 124)

Using the Integrated Development Environment UM013037-1212
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Zilog Developer Studio II – Z8 Encore!
User Manual
C run-time library functions) by compiling the function and then including the object mod-
ule name in this field. This is an alternative to including the source code for the revised
function explicitly in your project, which would also override the function in the default
run-time library.
C Start-Up Module
The buttons and checkbox in this area (which are not available for Assembly Only proj-
ects) control which start-up module is linked to your application. All C programs require
some initialization before the main function is called, which is typically done in a start-up
module.
Standard
If the Standard button is selected, the precompiled start-up module shipped with ZDS II is
used. This standard start-up module performs a minimum amount of initialization to pre-
pare the run-time environment as required by the ANSI C Standard and also does some
Z8 Encore!-specific configuration such as interrupt vector table initialization. See the
Lan-
guage Extensions section on page 194 for full details of the operations performed in the
standard start-up module.
Some of these steps carried out in the standard start-up module might not be required for
every application, so if code space is extremely tight, you might want to make some judi-
cious modifications to the start-up code. The source code for the start-up module is located
in the following file:
<ZDS Installation Directory>\src\boot\common\startupX.asm
In the above filepath, <ZDS Installation Directory> is the directory in which Zilog Devel-
oper Studio was installed. By default, this path is:
C:\Program Files\Zilog\ZDSII_Z8Encore!_
In the above filepath, <version> may be 4.11.0 or 5.0.0. The X in startupX.asm is s
for the small model or l for the large model.
Included in Project
If the Included in Project button is selected, then the standard start-up module is not
linked to your application. In this case, you are responsible for including suitable start-up
code, either by including the source code in the
Project Workspace window or by includ-
ing a precompiled object module in the Additional Object/Library Modules field. If you
modify the standard start-up module to tailor it to your project, you must select the
Included in Project button for your changes to take effect.
While you are responsible for writing your own start-up code when selecting this option,
ZDS II automatically inserts some needed linker commands into your linker command file.