PCF8563TS Philips Semiconductors, PCF8563TS Datasheet - Page 7

• Manufacturer Part Number: PCF8563TS
• Description: Real-time clock/calendar
• Manufacturer: Philips Semiconductors

Philips Semiconductors
9397 750 04855
Product specification
8.6.2 Control/Status 2 register
Table 7:
Table 8:
[1]
[2]
Table 9:
Bit
7 to 5
4
3
2
1
0
Source clock (Hz)
4 096
64
1
1
R/W
Read
Write
60
TF and INT become active simultaneously.
n = loaded countdown timer value. Timer stopped when n = 0.
Bit: AF
Value Description
0
1
0
1
Description of Control/Status 2 register bits description (address 01H)
INT operation (bit TI/TP = 1)
Value descriptions for bits AF and TF
Symbol Description
0
TI/TP
AF
TF
AIE
TIE
alarm flag inactive
alarm flag active
alarm flag is cleared
alarm flag remains unchanged
By default set to logic 0.
TI/TP = 0: INT is active when TF is active (subject to the status of TIE).
TI/TP = 1: INT pulses active according to
of TIE). Note that if AF and AIE are active then INT will be permanently
active.
When an alarm occurs, AF is set to logic 1. Similarly, at the end of a
timer countdown, TF is set to logic 1. These bits maintain their value
until overwritten by software. If both timer and alarm interrupts are
required in the application, the source of the interrupt can be
determined by reading these bits. To prevent one flag being
overwritten while clearing another, a logic AND is performed during a
write access. See
Bits AIE and TIE activate or deactivate the generation of an interrupt
when AF or TF is asserted, respectively. The interrupt is the logical OR
of these two conditions when both AIE and TIE are set.
AIE = 0: alarm interrupt disabled; AIE = 1: alarm interrupt enabled.
TIE = 0: timer interrupt disabled; TIE = 1: timer interrupt enabled.
16 April 1999
INT
[1]
period (s)
n
Table 9
1
[2]
1
1
1
8192
128
64
64
= 1
Bit: TF
Value Description
for the value descriptions of bits AF and TF.
0
1
0
1
timer flag inactive
timer flag active
timer flag is cleared
timer flag remains unchanged
Table 8
Real-time clock/calendar
© Philips Electronics N.V. 1999. All rights reserved.
(subject to the status
PCF8563
n > 1
1
1
1
1
4096
64
64
64
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