git.sur5r.net Git - cc65/blob - libsrc/c64/gettime.s

   1 ;
   2 ; Stefan Haubenthal, 27.7.2009
   3 ; Oliver Schmidt, 14.8.2018
   4 ;
   5 ; int clock_gettime (clockid_t clk_id, struct timespec *tp);
   6 ;
   7
   8         .include        "time.inc"
   9         .include        "c64.inc"
  10         .include        "get_tv.inc"
  11
  12         .constructor    inittime
  13         .importzp       sreg, tmp1, tmp2
  14         .import         pushax, pusheax, tosmul0ax, steaxspidx, incsp1, return0
  15         .import         _get_tv, _get_ostype
  16
  17
  18 ;----------------------------------------------------------------------------
  19 .code
  20
  21 .proc   _clock_gettime
  22
  23         jsr     pushax
  24         jsr     pushax
  25
  26         lda     CIA1_TODHR
  27         bpl     AM
  28         and     #%01111111
  29         sed
  30         clc
  31         adc     #$12
  32         cld
  33 AM:     jsr     BCD2dec
  34         sta     TM + tm::tm_hour
  35         lda     CIA1_TODMIN
  36         jsr     BCD2dec
  37         sta     TM + tm::tm_min
  38         lda     CIA1_TODSEC
  39         jsr     BCD2dec
  40         sta     TM + tm::tm_sec
  41         lda     #<TM
  42         ldx     #>TM
  43         jsr     _mktime
  44
  45         ldy     #timespec::tv_sec
  46         jsr     steaxspidx      ; Pops address pushed by 2. pushax
  47
  48         lda     #<(100 * 1000 * 1000 / $10000)
  49         ldx     #>(100 * 1000 * 1000 / $10000)
  50         sta     sreg
  51         stx     sreg+1
  52         lda     #<(100 * 1000 * 1000)
  53         ldx     #>(100 * 1000 * 1000)
  54         jsr     pusheax
  55         lda     CIA1_TOD10
  56         ldx     #>$0000
  57         jsr     tosmul0ax
  58
  59         ldy     #timespec::tv_nsec
  60         jsr     steaxspidx      ; Pops address pushed by 1. pushax
  61
  62         jsr     incsp1
  63         jmp     return0
  64
  65 .endproc
  66
  67 ;----------------------------------------------------------------------------
  68 ; dec = (((BCD>>4)*10) + (BCD&0xf))
  69
  70 .proc   BCD2dec
  71
  72         tax
  73         and     #%00001111
  74         sta     tmp1
  75         txa
  76         and     #%11110000      ; *16
  77         lsr                     ; *8
  78         sta     tmp2
  79         lsr
  80         lsr                     ; *2
  81         adc     tmp2            ; = *10
  82         adc     tmp1
  83         rts
  84
  85 .endproc
  86
  87 ;----------------------------------------------------------------------------
  88 ; Constructor that writes to the 1/10 sec register of the TOD to kick it
  89 ; into action. If this is not done, the clock hangs. We will read the register
  90 ; and write it again, ignoring a possible change in between.
  91 .segment "ONCE"
  92
  93 .proc   inittime
  94
  95         lda     CIA1_TOD10
  96         sta     CIA1_TOD10
  97         jsr     _get_tv
  98         cmp     #TV::PAL
  99         bne     @60Hz
 100         jsr     _get_ostype
 101         cmp     #$43
 102         beq     @60Hz
 103         lda     CIA1_CRA
 104         ora     #$80
 105         sta     CIA1_CRA
 106 @60Hz:  rts
 107
 108 .endproc
 109
 110 ;----------------------------------------------------------------------------
 111 ; TM struct with date set to 1970-01-01
 112 .data
 113
 114 TM:     .word           0       ; tm_sec
 115         .word           0       ; tm_min
 116         .word           0       ; tm_hour
 117         .word           1       ; tm_mday
 118         .word           0       ; tm_mon
 119         .word           70      ; tm_year
 120         .word           0       ; tm_wday
 121         .word           0       ; tm_yday
 122         .word           0       ; tm_isdst