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#ifndef _RTC_H
#define _RTC_H
/** @file
*
* CMOS Real-Time Clock (RTC)
*
* The CMOS/RTC registers are documented (with varying degrees of
* accuracy and consistency) at
*
* http://www.nondot.org/sabre/os/files/MiscHW/RealtimeClockFAQ.txt
* http://wiki.osdev.org/RTC
* http://wiki.osdev.org/CMOS
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <pic8259.h>
/** RTC IRQ */
#define RTC_IRQ 8
/** RTC interrupt vector */
#define RTC_INT IRQ_INT ( RTC_IRQ )
/** CMOS/RTC address (and NMI) register */
#define CMOS_ADDRESS 0x70
/** NMI disable bit */
#define CMOS_DISABLE_NMI 0x80
/** CMOS/RTC data register */
#define CMOS_DATA 0x71
/** RTC seconds */
#define RTC_SEC 0x00
/** RTC minutes */
#define RTC_MIN 0x02
/** RTC hours */
#define RTC_HOUR 0x04
/** RTC weekday */
#define RTC_WDAY 0x06
/** RTC day of month */
#define RTC_MDAY 0x07
/** RTC month */
#define RTC_MON 0x08
/** RTC year */
#define RTC_YEAR 0x09
/** RTC status register A */
#define RTC_STATUS_A 0x0a
/** RTC update in progress bit */
#define RTC_STATUS_A_UPDATE_IN_PROGRESS 0x80
/** RTC status register B */
#define RTC_STATUS_B 0x0b
/** RTC 24 hour format bit */
#define RTC_STATUS_B_24_HOUR 0x02
/** RTC binary mode bit */
#define RTC_STATUS_B_BINARY 0x04
/** RTC Periodic Interrupt Enabled bit */
#define RTC_STATUS_B_PIE 0x40
/** RTC status register C */
#define RTC_STATUS_C 0x0c
/** RTC status register D */
#define RTC_STATUS_D 0x0d
/** CMOS default address */
#define CMOS_DEFAULT_ADDRESS RTC_STATUS_D
#endif /* _RTC_H */