src/gmxlib/delay.s

   1 //
   2 //      @(#) delay.s 1.5 11/5/92
   3 //
   4 //
   5 //      GROMACS - Groningen Machine for Chemical Simulation
   6 //      Copyright (c) 1990, 1991, 1992, Groningen University
   7 //
   8 // Delay routine for the SPC-i860 by A. Sijbers, (c) 1991,1992
   9 //
  10 // General description:
  11 //
  12 // The routine delay(ms) delays for the number of milli seconds, specified
  13 // in the argument. This routine is written in assembler to be independent
  14 // of compiler options and optimalisations. Caching effects are ignored.
  15 //
  16 // C-interface:
  17 //
  18 //   extern void delay(int ms)
  19 //      Delays for ms milli seconds.
  20 //
  21 .globl  _delay
  22 .globl  _delay01
  23 //
  24 //   extern void delay(int ms)
  25 //      delays for ms milli seconds.
  26 //   extern void delay01(int ms01)
  27 //      delays for ms 0.01 milli seconds.
  28 //    in:
  29 //       r16 = ms
  30 //    modifies:
  31 //       r16,r17,r18
  32 //
  33 MS_LOOP         =       6666    // Experimental value for loop count,
  34                                 // accuracy: 1 percent
  35 //
  36 _delay:
  37         adds    1,r0,r18        // decrement
  38         subs    0,r16,r0
  39         bnc     delay_done
  40         subs    r16,r18,r16
  41         mov     MS_LOOP,r17
  42 loop:
  43         subs    0,r17,r0
  44         bnc     _delay
  45         subs    r17,r18,r17
  46         br      loop
  47         nop
  48 delay_done:
  49         bri r1
  50         nop
  51 //
  52 MS01_LOOP       =       66      // Experimental value for loop count,
  53                                 // accuracy: 1 percent
  54 //
  55 _delay01:
  56         adds    1,r0,r18        // decrement
  57         subs    0,r16,r0
  58         bnc     delay01_done
  59         subs    r16,r18,r16
  60         mov     MS01_LOOP,r17
  61 loop01:
  62         subs    0,r17,r0
  63         bnc     _delay01
  64         subs    r17,r18,r17
  65         br      loop01
  66         nop
  67 delay01_done:
  68         bri r1
  69         nop
  70 //