freebsd-src/usr.bin/doscmd/timer.c
John Dyson 90c38ed200 Add our doscmd to the tree. This is a result of work from BSDI, and
a group of dos emulator developers.
Submitted by:	Jonathan Lemon <jlemon@americantv.com>
Obtained from:	BSDI
1997-08-09 01:43:15 +00:00

51 lines
952 B
C

/*
** No copyright?!
**
** $Id: timer.c,v 1.3 1996/09/22 15:42:59 miff Exp $
*/
#include "doscmd.h"
static void
int08(regcontext_t *REGS)
{
softint(0x1c);
}
static void
int1c(regcontext_t *REGS)
{
}
unsigned char timer;
static u_char
inb_timer(int port)
{
return (--timer);
}
void
timer_init(void)
{
u_long vec;
struct itimerval itv;
vec = insert_hardint_trampoline();
ivec[0x08] = vec;
register_callback(vec, int08, "int 08");
vec = insert_softint_trampoline();
ivec[0x1c] = vec;
register_callback(vec, int1c, "int 1c");
define_input_port_handler(0x42, inb_timer);
define_input_port_handler(0x40, inb_timer);
itv.it_interval.tv_sec = 0;
itv.it_interval.tv_usec = 54925; /* 1193182/65536 times per second */
itv.it_value.tv_sec = 0;
itv.it_value.tv_usec = 54925; /* 1193182/65536 times per second */
if (! timer_disable)
setitimer(ITIMER_REAL, &itv, 0);
}