YRBASE
year = BCD_TO_BYTE(mostek[6]) + YRBASE;
tod.tod_year -= YRBASE;
tod.tod_year += 100 + YRBASE; /* 20xx year */
tod.tod_year += YRBASE; /* 19xx year */
tod.tod_year = BCD_TO_BYTE(CLOCK->clk_year) + YRBASE;
CLOCK->clk_year = BYTE_TO_BCD(tod.tod_year - YRBASE);