ARM 嵌入式 系统 设计与实例开发 实验教材 二源码

				/* mc146818rtc.h - register definitions for the Real-Time-Clock / CMOS RAM				 * Copyright Torsten Duwe  1993				 * derived from Data Sheet, Copyright Motorola 1984 (!).				 * It was written to be part of the Linux operating system.				 */				/* permission is hereby granted to copy, modify and redistribute this code				 * in terms of the GNU Library General Public License, Version 2 or later,				 * at your option.				 */								#ifndef _MC146818RTC_H				#define _MC146818RTC_H								#include 				#include 			/* get the user-level API */				#include 		/* spinlock_t */				#include 		/* register access macros */								extern spinlock_t rtc_lock;		/* serialize CMOS RAM access */								/**********************************************************************				 * register summary				 **********************************************************************/				#define RTC_SECONDS		0				#define RTC_SECONDS_ALARM	1				#define RTC_MINUTES		2				#define RTC_MINUTES_ALARM	3				#define RTC_HOURS		4				#define RTC_HOURS_ALARM		5				/* RTC_*_alarm is always true if 2 MSBs are set */				# define RTC_ALARM_DONT_CARE 	0xC0								#define RTC_DAY_OF_WEEK		6				#define RTC_DAY_OF_MONTH	7				#define RTC_MONTH		8				#define RTC_YEAR		9								/* control registers - Moto names				 */				#define RTC_REG_A		10				#define RTC_REG_B		11				#define RTC_REG_C		12				#define RTC_REG_D		13								/**********************************************************************				 * register details				 **********************************************************************/				#define RTC_FREQ_SELECT	RTC_REG_A								/* update-in-progress  - set to "1" 244 microsecs before RTC goes off the bus,				 * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,				 * totalling to a max high interval of 2.228 ms.				 */				# define RTC_UIP		0x80				# define RTC_DIV_CTL		0x70				   /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */				#  define RTC_REF_CLCK_4MHZ	0x00				#  define RTC_REF_CLCK_1MHZ	0x10				#  define RTC_REF_CLCK_32KHZ	0x20				   /* 2 values for divider stage reset, others for "testing purposes only" */				#  define RTC_DIV_RESET1	0x60				#  define RTC_DIV_RESET2	0x70				  /* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */				# define RTC_RATE_SELECT 	0x0F								/**********************************************************************/				#define RTC_CONTROL	RTC_REG_B				# define RTC_SET 0x80		/* disable updates for clock setting */				# define RTC_PIE 0x40		/* periodic interrupt enable */				# define RTC_AIE 0x20		/* alarm interrupt enable */				# define RTC_UIE 0x10		/* update-finished interrupt enable */				# define RTC_SQWE 0x08		/* enable square-wave output */				# define RTC_DM_BINARY 0x04	/* all time/date values are BCD if clear */				# define RTC_24H 0x02		/* 24 hour mode - else hours bit 7 means pm */				# define RTC_DST_EN 0x01	/* auto switch DST - works f. USA only */								/**********************************************************************/				#define RTC_INTR_FLAGS	RTC_REG_C				/* caution - cleared by read */				# define RTC_IRQF 0x80		/* any of the following 3 is active */				# define RTC_PF 0x40				# define RTC_AF 0x20				# define RTC_UF 0x10								/**********************************************************************/				#define RTC_VALID	RTC_REG_D				# define RTC_VRT 0x80		/* valid RAM and time */				/**********************************************************************/								/* example: !(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) 				 * determines if the following two #defines are needed				 */				#ifndef BCD_TO_BIN				#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)				#endif								#ifndef BIN_TO_BCD				#define BIN_TO_BCD(val) ((val)=(((val)/10)				#endif								#endif /* _MC146818RTC_H */