nes-proj/platform/apple2enh/sys/clock.c

79 lines
2.7 KiB
C

/*
* Copyright (c) 2007, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* Author: Oliver Schmidt <ol.sc@web.de>
*
* $Id: clock.c,v 1.2 2007/12/16 13:11:46 oliverschmidt Exp $
*/
#include <apple2.h>
#include "contiki.h"
#include "sys/log.h"
/* The enhanced Apple//e doesn't have a hardware clock whatsoever. Therefore the
* cc65 C-library for this target doesn't include an implementation of clock().
*/
static unsigned char tick = 14;
static clock_time_t time;
/*-----------------------------------------------------------------------------------*/
void
clock_init(void)
{
if(get_ostype() >= APPLE_IIGS) {
if(*(signed char *)0xC036 < 0) {
/* 5 / 14 = 1.0MHz / 2.8MHz */
tick = 5;
log_message("Assuming 2.8 MHz ...", "");
}
}
}
/*-----------------------------------------------------------------------------------*/
void
clock_update(void)
{
static unsigned int count;
count += tick;
if(count > 2000) {
count = 0;
++time;
}
}
/*-----------------------------------------------------------------------------------*/
clock_time_t
clock_time(void)
{
return time;
}
/*-----------------------------------------------------------------------------------*/