RTC_CENTURY_MASK
century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
century = ds1685_rtc_bcd2bin(rtc, century, RTC_CENTURY_MASK,
RTC_CENTURY_MASK);
RTC_CENTURY_MASK, RTC_CENTURY_MASK);
cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;