V3022 EMMICRO [EM Microelectronic - MARIN SA], V3022 Datasheet - Page 8

• Manufacturer Part Number: V3022
• Description: Very Low Power 8-Bit 32 kHz RTC Module with Digital Trimming and High Level Integration
• Manufacturer: EMMICRO [EM Microelectronic - MARIN SA]

Pin Description
SO28 Package
Functional Description
Data Retention and Standby
The V3022 is put in standby mode by activating the PF
input. When pulled logic low, PF will disable the input
lines, and immediately take to high impedance the lines
AD 0-7. Input states must be under control whenever PF
is deactivated.
provided, PF can be tied to the system RESET . Even in
standby the interrupt request pin IRQ will pull to ground
upon an unmasked alarm interrupt occurring.
Copyright © 2004, EM Microelectronic-Marin SA
Pin
1
2
3
4
5
6
7
8
9
10-14
15-19
20
21
22
23
24
25
26
27
28
Name
TEST
AD0
AD1
NC
AD2
AD3
V
V
AD4
NC
AD5
AD6
AD7
NC
PF
IRQ
RD
A /D
CS
WR
SS
DD
R
If no specific power fail signal can be
Description
Do not connect, factory test
pin
Power fail
Bit 0 from MUX address / data
bus
Bit 1 from MUX address / data
bus
No connection
Bit 2 from MUX address / data
bus
Bit 3 from MUX address / data
bus
Address / data decode
Interrupt request
Supply ground (substrate)
Positive supply terminal
Chip select
(Motorola)
Bit 4 from MUX address / data
bus
No connection
Bit 5 from MUX address / data
bus
Bit 6 from MUX address / data
bus
Bit 7 from MUX address / data
bus
No connection
RD (Intel) or DS (Motorola)
WR (Intel) or R/ W
Table 5
GND
PWR
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
O
-
-
-
I
I
I
I
I
I
Initialisation
When power is first applied to the V3022 all registers have
a random value.
To initialise the V3022, software must first write a 1 to the
initialisation bit (addr. 2 bit 4) and then a 0. This sets the
Frequency Tuning bit and clears all other status bits.
The time and date parameters should then be loaded into
the RAM (addr. 20 to 28 hex) and then transferred to the
reserved clock area using the clock command followed by
a write.
The digital trimming register must then be initialised
by writing 210 (D2 hex) to it, if Frequency Tuning is
not required.
digital trimming register the frequency tuning mode
bit can be cleared.
RAM Configuration
The RAM area of the V3022 has a reserved clock and
time area, a data space, and an address command space
(see Table 9 or Fig. 7). The reserved clock and timer
area is not directly accessible to the user, it is used for
internal time keeping and contains the current time and
date plus the timer parameters.
Data Space
All locations in the data space are Read/Write. The data
space is directly accessible to the user and is divided into
five areas:
Status Registers – three registers used for status and
control data for the device (see Table 6, 7 and 8).
Digital Trimming Register – a special function described
under "Frequency Tuning".
Time and Date Registers – nine time and date locations
which are loaded with, either the current time and date
parameters from the reserved clock area or the time and
date parameters to be transferred to the reserved clock
area.
Alarm Registers – five locations used for setting the
alarm parameters.
Timer Registers – four locations which are loaded with
either the timer parameters from the reserved timer area
or the timer parameters to be transferred to the reserved
timer area.
8
After having written a value to the
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V3022