arch/m68k-amiga/lowlevel/starttimerint.c

   1 /*
   2     Copyright © 2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <aros/libcall.h>
   7
   8 #include <proto/lowlevel.h>
   9 #include <proto/cia.h>
  10
  11 #include <exec/types.h>
  12 #include <libraries/lowlevel.h>
  13 #include <hardware/cia.h>
  14 #include <resources/cia.h>
  15
  16 #include "lowlevel_intern.h"
  17 #include "cia_intern.h"
  18 #include "cia_timer.h"
  19
  20 AROS_LH3(VOID, StartTimerInt,
  21       AROS_LHA(APTR , intHandle, A1),
  22       AROS_LHA(ULONG, timeInterval, D0),
  23       AROS_LHA(BOOL , continuous, D1),
  24       struct LowLevelBase *, LowLevelBase, 16, LowLevel)
  25 {
  26     AROS_LIBFUNC_INIT
  27
  28     struct CIABase *CiaBase = (struct CIABase *)LowLevelBase->ll_CIA.llciat_Base;
  29     UBYTE volatile *ciacr_ptr;
  30     UBYTE crflags;
  31     long long ecv;
  32
  33     if (intHandle && (timeInterval > 0))
  34     {
  35         /* Stop the timer if it is currently running */
  36         StopTimerInt(intHandle);
  37
  38         /* convert to EClock's */
  39         ecv = ((long long)timeInterval * LowLevelBase->ll_EClockMult) >> 15;
  40         if ((ecv & 0xFFFF) == 0)
  41             ecv = 1;
  42
  43         /*
  44          * Set the requested interval, and Choose appropriate flags
  45          * for the used CIA timer...
  46          */
  47         if (LowLevelBase->ll_CIA.llciat_iCRBit == CIAICRB_TA)
  48         {
  49             CiaBase->hw->ciatalo = (ecv & 0xFF);
  50             CiaBase->hw->ciatahi = ((ecv >> 8) & 0xFF);
  51
  52             ciacr_ptr = &CiaBase->hw->ciacra;
  53             crflags = CIASTART_A;
  54             if (!continuous)
  55                 crflags |= CIACRAF_RUNMODE;
  56         }
  57         else
  58         {
  59             CiaBase->hw->ciatblo = (ecv & 0xFF);
  60             CiaBase->hw->ciatbhi = ((ecv >> 8) & 0xFF);
  61
  62             ciacr_ptr = &CiaBase->hw->ciacrb;
  63             crflags = CIASTART_B;
  64             if (!continuous)
  65                 crflags |=  CIACRBF_RUNMODE;
  66         }
  67
  68         /* .. and start up the timer */
  69         *ciacr_ptr |= crflags;
  70     }
  71
  72     return;
  73
  74     AROS_LIBFUNC_EXIT
  75 }