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23 lines
343 B
C
23 lines
343 B
C
/* See COPYRIGHT for copyright information. */
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/* Support for reading the NVRAM from the real-time clock. */
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#include <inc/x86.h>
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#include <kern/kclock.h>
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unsigned
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mc146818_read(unsigned reg)
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{
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outb(IO_RTC, reg);
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return inb(IO_RTC+1);
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}
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void
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mc146818_write(unsigned reg, unsigned datum)
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{
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outb(IO_RTC, reg);
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outb(IO_RTC+1, datum);
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}
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