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   1         ;; Generic crt0.s for a Z80
   2         .module crt0
   3         .globl  _main
   4
   5         .area _HEADER (ABS)
   6         ;; Reset vector
   7         .org    0
   8         jp      init
   9
  10         .org    0x08
  11         reti
  12         .org    0x10
  13         reti
  14         .org    0x18
  15         reti
  16         .org    0x20
  17         reti
  18         .org    0x28
  19         reti
  20         .org    0x30
  21         reti
  22         .org    0x38
  23         reti
  24
  25         .org    0x100
  26 init:
  27         ;; Stack at the top of memory.
  28         ld      sp,#0xffff
  29
  30         ;; Initialise global variables
  31         call    gsinit
  32         call    _main
  33         jp      _exit
  34
  35         ;; Ordering of segments for the linker.
  36         .area   _CODE
  37         .area   _GSINIT
  38         .area   _GSFINAL
  39
  40         .area   _DATA
  41         .area   _BSS
  42         .area   _HEAP
  43
  44         .area   _CODE
  45 __clock::
  46         ld      a,#2
  47         rst     0x08
  48         ret
  49
  50 _exit::
  51         ;; Exit - special code to the emulator
  52         ld      a,#0
  53         rst     0x08
  54 1$:
  55         halt
  56         jr      1$
  57
  58         .area   _GSINIT
  59 gsinit::
  60
  61         .area   _GSFINAL
  62         ret