git.sur5r.net Git - cc65/blob - libsrc/cbm510/waitvsync.s

   1 ;
   2 ; Written by Groepaz <groepaz@gmx.net>
   3 ;
   4 ; void waitvsync (void);
   5 ;
   6
   7         .export         _waitvsync
   8         .import         PALFLAG
   9         .import         sys_bank, restore_bank
  10
  11         .importzp       vic
  12
  13         .include        "cbm510.inc"
  14
  15 _waitvsync:
  16         jsr     sys_bank        ; Switch to the system bank
  17         sei
  18
  19         ldy     #VIC_CTRL1
  20 @l1:
  21         lda     (vic),y
  22         bpl     @l1
  23 @l2:
  24         lda     (vic),y
  25         bmi     @l2
  26
  27         cli
  28         jmp    restore_bank