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SBASIC Manual - Page 49

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     SBasic User's Manual     SBasic Version 2.7             Page 49
     Printed:  December 5, 1999
     force the vectors to appear at the proper locations, and also to force
     the library routines to compile in the correct locations, I had to use
     the third variation of the ORG statement above.

     For example, I compiled the following portions of code using a /c
     option of $f700:

          org  $8000  code    ' redefine code section here
     main:
          n = 14              ' this is the mainline code
          ...                 ' rest of mainline code goes here

          org  $f7e8          ' address of RTI vector
          asm                 ' switch to assembly language
          jmp  _rtiisr        use an assembly JMP instruction
          endasm              ' back to SBasic

          org  code           ' return to code section

          end                 ' end of program

     The /cf700 option started compilation with the code section at $f700.
     This caused SBasic to write the startup library code at $f700.  The
     ORG $8000 statement then moved MAIN down to $8000 and also caused the
     code section to move to that address.  The rest of the mainline code
     (not shown here) compiled from there.

     Next, the ORG $f7e8 let me write a JMP instruction into the
     bootloader's vector area for use by the RTI interrupt.  Finally, the
     ORG CODE statement switched back to the code section, now somewhere
     above $8000.

     This last step is important.  SBasic automatically switches to the
     code section before adding any library files at the end of the
     compilation.  If I hadn't moved the code section to $8000, SBasic
     would have added the library files at $f700, which was the original
     code section.  The resulting executable file would have failed.