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authorBrian Paul <[email protected]>2002-02-12 03:24:06 +0000
committerBrian Paul <[email protected]>2002-02-12 03:24:06 +0000
commitcc27365d775632647a1d07d78203421d27e8cd1c (patch)
tree6ead1990c2b13c98e0a2e0060cb2037685e7c820 /src/glut/dos/PC_HW/pc_timer.c
parentbcb148de9201c7f90a68c7c46434e7ebf7204000 (diff)
Daniel Borca's GLUT for DOS/DGJPP.
Diffstat (limited to 'src/glut/dos/PC_HW/pc_timer.c')
-rw-r--r--src/glut/dos/PC_HW/pc_timer.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/src/glut/dos/PC_HW/pc_timer.c b/src/glut/dos/PC_HW/pc_timer.c
new file mode 100644
index 00000000000..a8c58f67418
--- /dev/null
+++ b/src/glut/dos/PC_HW/pc_timer.c
@@ -0,0 +1,158 @@
+/*
+ * PC/HW routine collection v0.1 for DOS/DJGPP
+ *
+ * Copyright (C) 2002 - Borca Daniel
+ * Email : [email protected]
+ * Web : http://www.geocities.com/dborca
+ */
+
+
+#include <pc.h>
+
+#include "pc_hw.h"
+
+#define TIMER_IRQ 0
+
+#define MAX_TIMERS 8
+
+#define PIT_FREQ 0x1234DD
+
+#define unvolatile(__v, __t) __extension__ ({union { volatile __t __cp; __t __p; } __q; __q.__cp = __v; __q.__p;})
+
+static int timer_installed;
+
+typedef struct {
+ volatile unsigned int counter, clock_ticks, freq;
+ volatile PFUNC func;
+ volatile void *parm;
+} TIMER;
+
+TIMER timer_main, timer_func[MAX_TIMERS];
+
+static int timer ()
+{
+ int i;
+
+ for (i=0;i<MAX_TIMERS;i++) {
+ TIMER *t = &timer_func[i];
+ if (t->func) {
+ t->clock_ticks += t->counter;
+ if (t->clock_ticks>=timer_main.counter) {
+ t->clock_ticks -= timer_main.counter;
+ t->func(unvolatile(t->parm, void *));
+ }
+ }
+ }
+
+ timer_main.clock_ticks += timer_main.counter;
+ if (timer_main.clock_ticks>=0x10000) {
+ timer_main.clock_ticks -= 0x10000;
+ return 1;
+ } else {
+ outportb(0x20, 0x20);
+ return 0;
+ }
+} ENDOFUNC(timer)
+
+void pc_remove_timer (void)
+{
+ if (timer_installed) {
+ timer_installed = FALSE;
+ pc_clexit(pc_remove_timer);
+
+ DISABLE();
+ outportb(0x43, 0x34);
+ outportb(0x40, 0);
+ outportb(0x40, 0);
+ ENABLE();
+
+ pc_remove_irq(TIMER_IRQ);
+ }
+}
+
+static int install_timer (void)
+{
+ if (timer_installed||pc_install_irq(TIMER_IRQ, timer)) {
+ return -1;
+ } else {
+ LOCKDATA(timer_func);
+ LOCKDATA(timer_main);
+ LOCKFUNC(timer);
+
+ timer_main.counter = 0x10000;
+
+ DISABLE();
+ outportb(0x43, 0x34);
+ outportb(0x40, 0);
+ outportb(0x40, 0);
+ timer_main.clock_ticks = 0;
+ ENABLE();
+
+ pc_atexit(pc_remove_timer);
+ timer_installed = TRUE;
+ return 0;
+ }
+}
+
+static TIMER *find_slot (PFUNC func)
+{
+ int i;
+
+ for (i=0;i<MAX_TIMERS;i++) {
+ if (timer_func[i].func==func) {
+ return &timer_func[i];
+ }
+ }
+ for (i=0;i<MAX_TIMERS;i++) {
+ if (!timer_func[i].func) {
+ return &timer_func[i];
+ }
+ }
+
+ return NULL;
+}
+
+int pc_install_int (PFUNC func, void *parm, unsigned int freq)
+{
+ int i;
+ TIMER *t;
+
+ if (!timer_installed) {
+ if (install_timer()) {
+ return -1;
+ }
+ }
+
+ if ((t=find_slot(func))!=NULL) {
+ unsigned int new_counter = PIT_FREQ / freq;
+
+ DISABLE();
+
+ t->func = func;
+ t->parm = parm;
+ t->freq = freq;
+ t->clock_ticks = 0;
+
+ if (new_counter < timer_main.counter) {
+ for (i=0;i<MAX_TIMERS;i++) {
+ if (timer_func[i].func) {
+ timer_func[i].counter = new_counter * timer_func[i].freq / freq;
+ }
+ }
+ outportb(0x43, 0x34);
+ outportb(0x40, (unsigned char)new_counter);
+ outportb(0x40, (unsigned char)(new_counter>>8));
+ timer_main.clock_ticks = 0;
+ timer_main.counter = new_counter;
+ timer_main.freq = freq;
+ } else {
+ t->counter = PIT_FREQ * freq / (timer_main.freq * timer_main.freq);
+ }
+
+ ENABLE();
+
+ return 0;
+ }
+
+ return -1;
+}