223cc6685e
git-svn-id: svn://svn.compuextreme.de/Viitor/V963/Viitor_cc65@5933 504e572c-2e33-0410-9681-be2bf7408885
50 lines
1.7 KiB
HTML
50 lines
1.7 KiB
HTML
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<TITLE>Commodore 128 specific information for cc65: Memory layout</TITLE>
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<H2><A NAME="s3">3.</A> <A HREF="c128.html#toc3">Memory layout</A></H2>
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<P>cc65 generated programs with the default setup run with the I/O area and the
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kernal ROM enabled. Note that this is a non standard memory layout, and that
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there is no "memory configuration index" for this layout. This means that
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special case has to be taken when changing the configuration, or calling any
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code that does this. The memory configuration register at $FF00 should
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be saved and restored instead of relying on the memory configuration index
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stored in the zero page.</P>
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<P>The setup gives a usable memory range of $1C00 - $CFFF. Having
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just the kernal ROM mapped in means, that kernal entry points may be called
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directly, but using the BASIC ROM is not possible without additional code.</P>
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<P>Special locations:</P>
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<P>
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<DL>
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<DT><B>Text screen</B><DD><P>The text screen is located at $400 (as in the standard setup).</P>
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<DT><B>Stack</B><DD><P>The C runtime stack is located at $CFFF and growing downwards.</P>
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<DT><B>Heap</B><DD><P>The C heap is located at the end of the program and grows towards the C
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runtime stack.</P>
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</DL>
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</P>
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