
5
FN1547
.8
October
29,
200
7
Functional Block Diagram
FREEZE
CIRCUIT
CE
LINE
50/60Hz
AM - PM AND
HOUR LOGIC
DAY/DAY
OF WEEK
OSCILLATOR
XTAL IN
XTAL OUT
VBATT
PRESCALE
SECOND
MINUTE
HOUR
CALENDAR
LOGIC
MONTH
PRESCALE
SELECT
CLOCK
SELECT
CLOCK
CONTROL
REGISTER
INTERRUPT
CONTROL
REGISTER
CLOCK
AND
INT
LOGIC
CLOCK
OUT
INT
VDD
VSS
POWER
SENSE
CONTROL
INT STATUS
REGISTER
LINE
PSE
VSYS
POR
CPUR
SCK
MISO
MOSI
COMPARATOR
SECOND
LATCH
MINUTE
LATCH
HOUR
LATCH
32x8
RAM
SERIAL
INTERFACE
YEAR
8-BIT DATA BUS
FIGURE 1. REAL TIME CLOCK FUNCTIONAL DIAGRAM
CDP68HC68T1