MC68HC68T1 Datasheet, PDF (9/26 Pages) Motorola, Inc – Real-Time Clock plus RAM with Serial Interface

HEX ADDRESS
READ
WRITE DB7
$20
$A0
READ/WRITE REGISTERS
FUNCTION
DB0
TENS 0 – 5
UNITS 0 – 9
SECONDS (00 – 59)
$21
$A1
TENS 0 – 5
UNITS 0 – 9
MINUTES (00 – 59)
$22
$A2
12
HR
24
PM/AM
X _{TENS 0 – 2}
UNITS 0 – 9
DB7, 1 = 12 HR, 0 = 24 HR
DB5, 1 = PM, 0 = AM
HOURS (01 – 12 OR 00 – 23)
DAY OF WEEK (01 – 07)
$23
$A3
X
XXX
X UNITS 1 – 7
SUNDAY = 1
$24
$A4
TENS 0 – 3
UNITS 0 – 9
DATE OF MONTH (01 – 31)
$25
$A5
$26
$A6
TENS 0 – 1
TENS 0 – 9
UNITS 0 – 9
UNITS 0 – 9
MONTH (01 – 12)
JAN = 1
YEAR (00 – 99)
$31
$B1
7
65
4
3
2
1
0
CLOCK CONTROL REGISTER
$32
$B2
7
65
4
3
2
1
0
INTERRUPT CONTROL REGISTER
WRITE–ONLY REGISTERS
N/A
$A8
TENS 0 – 5
UNITS 0 – 9
SECONDS ALARM (00 – 59)
N/A
$A9
TENS 0 – 5
UNITS 0 – 9
MINUTES ALARM (00 – 59)
N/A
PM/AM
$AA
X
X _{TENS 0 – 2}
UNITS 0 – 9
HOURS ALARM (01 – 21 OR 00 – 23)
DB5, 1 = PM, 0 = AM IN 12 HR MODE
READ–ONLY REGISTER
$B0
N/A
7
65
4
3
2
1
0
STATUS REGISTER
RAM DATA BYTE
$00 T0 $1F $80 T0 $9F
D7
NOTE:
X = Don’t Care for Write
X = 0 for Read
N/A = Not Applicable
D6 D5 D4 D3 D2 D1 D0
Figure 6. Clock/RAM Registers
DATA
MOTOROLA
MC68HC68T1
9