src/device/c64x/c64x.s

   1 ;  /**
   2 ;   *  @file  c64x.s
   3 ;   *
   4 ;   *  @breif
   5 ;   *    Assembly functions for c64x compatible devices
   6 ;   */
   7
   8         .text
   9
  10 ; ********************************************************************************
  11 ; * Provide a rough delay, in CPU cycles.
  12 ; * On Entry:
  13 ; *   A4 = number of cycles to delay
  14 ; ********************************************************************************
  15         .def _chipDelay32
  16 _chipDelay32:
  17
  18                         ZERO    .L2       B4
  19                         SHRU    .S1   A4,3,A0
  20                         CMPLTU  .L2X  B4,A4,B0
  21         [!A0]   BNOP    .S1   cend, 5
  22
  23         [!B0]   BNOP    .S1   cend, 3
  24             MVKL    .S1   1,A5
  25                         MVKH    .S1       1,A5
  26
  27
  28 dosub:
  29                         SUB     .L1   A0,A5,A0
  30                         NOP             2
  31         [A0]    BNOP    .S1   dosub,5
  32
  33
  34
  35 cend:
  36                         RETNOP.S2  B3, 5
  37
  38
  39
  40
  41
  42