Rev 56 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 56 | pj | 1 | /* |
| 2 | * PC/HW routine collection v1.0 for DOS/DJGPP |
||
| 3 | * |
||
| 4 | * Copyright (C) 2002 - Borca Daniel |
||
| 5 | * Email : dborca@yahoo.com |
||
| 6 | * Web : http://www.geocities.com/dborca |
||
| 7 | */ |
||
| 8 | |||
| 9 | |||
| 10 | #include <pc.h> |
||
| 11 | |||
| 12 | #include "pc_hw.h" |
||
| 13 | |||
| 14 | #define TIMER_IRQ 0 |
||
| 15 | |||
| 16 | #define MAX_TIMERS 8 |
||
| 17 | |||
| 18 | #define PIT_FREQ 0x1234DD |
||
| 19 | |||
| 20 | #define unvolatile(__v, __t) __extension__ ({union { volatile __t __cp; __t __p; } __q; __q.__cp = __v; __q.__p;}) |
||
| 21 | |||
| 22 | static int timer_installed; |
||
| 23 | |||
| 24 | typedef struct { |
||
| 25 | volatile unsigned int counter, clock_ticks, freq; |
||
| 26 | volatile PFUNC func; |
||
| 27 | volatile void *parm; |
||
| 28 | } TIMER; |
||
| 29 | |||
| 30 | TIMER timer_main, timer_func[MAX_TIMERS]; |
||
| 31 | |||
| 32 | static int timer () |
||
| 33 | { |
||
| 34 | int i; |
||
| 35 | |||
| 36 | for (i=0;i<MAX_TIMERS;i++) { |
||
| 37 | TIMER *t = &timer_func[i]; |
||
| 38 | if (t->func) { |
||
| 39 | t->clock_ticks += t->counter; |
||
| 40 | if (t->clock_ticks>=timer_main.counter) { |
||
| 41 | t->clock_ticks -= timer_main.counter; |
||
| 42 | t->func(unvolatile(t->parm, void *)); |
||
| 43 | } |
||
| 44 | } |
||
| 45 | } |
||
| 46 | |||
| 47 | timer_main.clock_ticks += timer_main.counter; |
||
| 48 | if (timer_main.clock_ticks>=0x10000) { |
||
| 49 | timer_main.clock_ticks -= 0x10000; |
||
| 50 | return 1; |
||
| 51 | } else { |
||
| 52 | outportb(0x20, 0x20); |
||
| 53 | return 0; |
||
| 54 | } |
||
| 55 | } ENDOFUNC(timer) |
||
| 56 | |||
| 57 | void pc_remove_timer (void) |
||
| 58 | { |
||
| 59 | if (timer_installed) { |
||
| 60 | timer_installed = FALSE; |
||
| 61 | pc_clexit(pc_remove_timer); |
||
| 62 | |||
| 63 | DISABLE(); |
||
| 64 | outportb(0x43, 0x34); |
||
| 65 | outportb(0x40, 0); |
||
| 66 | outportb(0x40, 0); |
||
| 67 | ENABLE(); |
||
| 68 | |||
| 69 | pc_remove_irq(TIMER_IRQ); |
||
| 70 | } |
||
| 71 | } |
||
| 72 | |||
| 73 | static int install_timer (void) |
||
| 74 | { |
||
| 75 | if (timer_installed||pc_install_irq(TIMER_IRQ, timer)) { |
||
| 76 | return -1; |
||
| 77 | } else { |
||
| 78 | LOCKDATA(timer_func); |
||
| 79 | LOCKDATA(timer_main); |
||
| 80 | LOCKFUNC(timer); |
||
| 81 | |||
| 82 | timer_main.counter = 0x10000; |
||
| 83 | |||
| 84 | DISABLE(); |
||
| 85 | outportb(0x43, 0x34); |
||
| 86 | outportb(0x40, 0); |
||
| 87 | outportb(0x40, 0); |
||
| 88 | timer_main.clock_ticks = 0; |
||
| 89 | ENABLE(); |
||
| 90 | |||
| 91 | pc_atexit(pc_remove_timer); |
||
| 92 | timer_installed = TRUE; |
||
| 93 | return 0; |
||
| 94 | } |
||
| 95 | } |
||
| 96 | |||
| 97 | static TIMER *find_slot (PFUNC func) |
||
| 98 | { |
||
| 99 | int i; |
||
| 100 | |||
| 101 | for (i=0;i<MAX_TIMERS;i++) { |
||
| 102 | if (timer_func[i].func==func) { |
||
| 103 | return &timer_func[i]; |
||
| 104 | } |
||
| 105 | } |
||
| 106 | for (i=0;i<MAX_TIMERS;i++) { |
||
| 107 | if (!timer_func[i].func) { |
||
| 108 | return &timer_func[i]; |
||
| 109 | } |
||
| 110 | } |
||
| 111 | |||
| 112 | return NULL; |
||
| 113 | } |
||
| 114 | |||
| 115 | int pc_install_int (PFUNC func, void *parm, unsigned int freq) |
||
| 116 | { |
||
| 117 | int i; |
||
| 118 | TIMER *t; |
||
| 119 | |||
| 120 | if (!timer_installed) { |
||
| 121 | if (install_timer()) { |
||
| 122 | return -1; |
||
| 123 | } |
||
| 124 | } |
||
| 125 | |||
| 126 | if ((t=find_slot(func))!=NULL) { |
||
| 127 | unsigned int new_counter = PIT_FREQ / freq; |
||
| 128 | |||
| 129 | DISABLE(); |
||
| 130 | |||
| 131 | t->func = func; |
||
| 132 | t->parm = parm; |
||
| 133 | t->freq = freq; |
||
| 134 | t->clock_ticks = 0; |
||
| 135 | |||
| 136 | if (new_counter < timer_main.counter) { |
||
| 137 | for (i=0;i<MAX_TIMERS;i++) { |
||
| 138 | if (timer_func[i].func) { |
||
| 139 | timer_func[i].counter = new_counter * timer_func[i].freq / freq; |
||
| 140 | } |
||
| 141 | } |
||
| 142 | outportb(0x43, 0x34); |
||
| 143 | outportb(0x40, (unsigned char)new_counter); |
||
| 144 | outportb(0x40, (unsigned char)(new_counter>>8)); |
||
| 145 | timer_main.clock_ticks = 0; |
||
| 146 | timer_main.counter = new_counter; |
||
| 147 | timer_main.freq = freq; |
||
| 148 | } else { |
||
| 149 | t->counter = PIT_FREQ * freq / (timer_main.freq * timer_main.freq); |
||
| 150 | } |
||
| 151 | |||
| 152 | ENABLE(); |
||
| 153 | |||
| 154 | return 0; |
||
| 155 | } |
||
| 156 | |||
| 157 | return -1; |
||
| 158 | } |