source: buchla-68k/iolib/traps.s@ 0170798

| traps.s -- define trap linkages for C routines
| -------    -----------------------------------
| Version 8 -- 1987-06-08 -- D.N. Lynx Crowe

| Caution:  these are serially re-useable, but NOT reentrant, so
| don't use them in interrupt processing code.

| An exception is made for ROMP in _trap15 for breakpoints so that the
| debug code can be debugged.

                .text

                .xdef   _trap1
                .xdef   _trap13,_trap14
                .xdef   _xtrap15

                .xdef   tr1sav,tr13sav,tr14sav
                .xdef   tr1rmp,tr13rmp,tr14rmp

| _trap1 -- provide access to BDOS functions
| ------    --------------------------------
_trap1:         move.l  (a7)+,tr1sav            | Save return address
                trap    #1                      | Do the trap
                move.l  tr1sav,-(a7)            | Restore return address
                rts                             | Return to caller

| _trap13 -- provide access to BIOS functions
| -------    --------------------------------
_trap13:        move.l  (a7)+,tr13sav           | Save return address
                trap    #13                     | Do the trap
                move.l  tr13sav,-(a7)           | Restore return address
                rts                             | Return to caller

| _trap14 -- provide access to extended BIOS functions
| -------    -----------------------------------------
_trap14:        move.l  (a7)+,tr14sav           | Save return address
                trap    #14                     | Do the trap
                move.l  tr14sav,-(a7)           | Restore return address
                rts                             | Return to caller

| _xtrap15 -- Setup initial register trap for ROMP
| --------    ------------------------------------
_xtrap15:       trap    #15                     | TRAP into ROMP
                rts                             | Return  (usually won't happen)

                .page

| RAM storage areas
| -----------------
                .bss
                .even

tr1sav:         ds.l    1               | Return address for trap1
tr13sav:        ds.l    1               | Return address for trap13
tr14sav:        ds.l    1               | Return address for trap14

tr1rmp:         ds.l    1               | Save area for tr1sav for ROMP
tr13rmp:        ds.l    1               | Save area for tr13sav for ROMP
tr14rmp:        ds.l    1               | Save area for tr14sav for ROMP

                .end