2 ; Ullrich von Bassewitz, 27.09.1998
4 ; void set_brk (unsigned Addr);
5 ; void reset_brk (void);
8 .export _set_brk, _reset_brk
9 .export _brk_a, _brk_x, _brk_y, _brk_sr, _brk_pc
22 oldvec: .res 2 ; Old vector
26 uservec: jmp $FFFF ; Patched at runtime
31 ; Set the break vector
35 stx uservec+2 ; Set the user vector
37 lda #<brk_handler ; Set the break vector to our routine
46 ; Reset the break vector
51 sta brk_jmp+2 ; Reset the vector
58 ; Break handler, called if a break occurs.
69 and #$EF ; Clear break bit
73 sbc #2 ; Point to start of brk
79 jsr uservec ; Call the user's routine