Ampro Corporation 486E Battery-Backed Clock

Little Board™/486e Technical Manual
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Battery-Backed Clock
An AT-compatible battery-backed real-time clock (with CMOS RAM) is standard on the
Little Board/486e CPU. A 3.6-volt Lithium ba ttery c onne cted to the U tility Co nne ctor , J16, can
power the clock. Battery drain for the clock is less than 1 uA. This battery will support the clock for
about 10 years.
Use the Ampro SETUP utility to set the c ur rent time and date in the re al-tim e clo ck, as w ell as
SETUP information in the CMOS RAM portion of the clock chip (configuration memory).
The contents of the configuration memory are also stored in an onboard EEPROM. The ROM BIOS
reads the EEPROM to get configuration information if th e CMO S R AM data is lost. Thi s mean s
that the board functions without the ba ttery . Ho wev er, w ithou t a batte ry the re al-tim e clo ck d ate
and time will not be correct.