start68k.lib

来自「open source of basic interpreter of 68」· LIB 代码 · 共 35 行

*
*  start68k.lib      SBasic startup file for the 68000
*
*  This file is automatically included in every executable built by
*  the SBasic68k compiler.  It contains generic startup code for
*  any 68000 hardware that will run an SBasic68k executable.
*
*  Additionally, you can insert in this file any code that your particular
*  hardware needs to run prior to execution of the mainline SBasic68k
*  executable.  For example, you can put code in this file for moving
*  a vector table from ROM to RAM and for switching ROM out of the low
*  memory area.
*

*
*  The following register assignments are REQUIRED by SBasic.  Do not
*  change them or your SBasic executable will crash.  Registers not
*  assigned here may be used freely by your assembly language routines.
*
*  d0  -- working data register; passes arguments/results
*  d1  -- normally free; used in some data calculations
*  a0  -- working address register; holds temporary addresses
*  a1  -- normally free; used in some address calculations
*  a4  -- holds pointer to data stack
*  a5  -- holds pointer to variable area
*  a6  -- link register
*  a7  -- hardware stack register
*

		move.l		#stkbeg,a7		set stack pointer
		move.l		#varbeg,a5		set pointer to variable area
		move.l		#stkbeg-$100,a4		set start of data stack