pcf8593 NXP Semiconductors, pcf8593 Datasheet - Page 9

• Manufacturer Part Number: pcf8593
• Description: Low Power Clock/calendar
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Table 1 Cycle length of the time counters, clock modes.
7.5
When the alarm enable bit of the control/status register is
set (address 00, bit 2) the alarm control register
(address 08) is activated. All alarm, timer, and interrupt
output functions are controlled by the contents of the alarm
control register (see Fig.8).
7.6
All alarm registers are allocated with a constant address
offset of hexadecimal 08 to the corresponding counter
registers (see Fig.4,Register arrangement).
1997 Mar 25
Hundredths of a second
Seconds
Minutes
Hours (24 h)
Hours (12 h)
Date
Months
Year
Weekdays
Timer
Low power clock/calendar
Alarm control register
Alarm registers
UNIT
00 to 99
00 to 59
00 to 59
00 to 23
12 AM
01 AM to 11 AM
12 PM
01 PM to 11 PM
01 to 31
01 to 30
01 to 29
01 to 28
01 to 12
0 to 3
0 to 6
00 to 99
COUNTING CYCLE
9
99 to 00
59 to 00
59 to 00
23 to 00
11 PM to 12 AM
31 to 01
30 to 01
29 to 01
28 to 01
12 to 01
6 to 0
no carry
An alarm signal is generated when the contents of the
alarm registers matches bit-by-bit the contents of the
involved counter registers. The year and weekday bits are
ignored in a dated alarm. A daily alarm ignores the month
and date bits. When a weekday alarm is selected, the
contents of the alarm weekday/month register will select
the weekdays on which an alarm is activated (see Fig.9).
Remark: in the 12 h mode, bits 6 and 7 of the alarm hours
register must be the same as the hours counter.
CARRY TO NEXT UNIT
1, 3, 5, 7, 8, 10 and 12
4, 6, 9 and 11
2, year = 0
2, year = 1, 2 and 3
CONTENTS OF THE
MONTH COUNTER
Product specification
PCF8593