K A B T R O N I C S P A R T S I D E N T I F I C A T I O N
World Clock Kit Page 29
Theory of Operation
This clock is based on a temperature-compensated crystal oscillator (TCXO) with an output of
32.768KHz. After dividing by 256, a periodic interrupt at 128 Hz keeps time and date.
Once a minute, a message with the current UTC time is sent around the RS-232 signal loop
described in the configuration section.
Each display slice holds the local time offset, accounting for daylight savings, and computes the
local time.
The controller slice detects power loss and reconfigures the board for low power consumption,
keeping only the time base and processor active. On power restoration, all boards are
reconfigured and the time messages restart on the minute interval.
Summary of Contents for World Clock
Page 1: ...World Clock Operating and Assembly Manual...
Page 32: ...KABtronics S C H E M A T I C World Clock Kit Page 32 Circuit Board Views...
Page 34: ...KABtronics S C H E M A T I C World Clock Kit Page 34...
Page 35: ...KABtronics S C H E M A T I C World Clock Kit Page 35...
Page 36: ...KABtronics S C H E M A T I C World Clock Kit Page 36...
Page 37: ...KABtronics S C H E M A T I C World Clock Kit Page 37...
