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FUNCTIONAL ARCHITECTURE
2
- Data
3
+ Data
4
Ground
Cable ground
2.9.6.
Real-Time Clock
The integrated Real Time Clock (RTC) is DS12887/MC146818 compatible
and provides the time of day clock, 100-year calendar with alarm features
and is accurate to within 1 minute per month, it consumes less than 1
µ
A of
standby current (Typ.). The (RTC) supports 256 bytes of battery backed
Non-volatile CMOS memory in two banks of 128 bytes each, both banks
being reserved for BIOS use. One bank of CMOS memory is used to
maintain the clock and user-system-setting configuration parameters when
the main system power is removed. The other bank (128 bytes) is lockable
in 4x32 byte blocks and can be used to store and lock miscellaneous
information.
The CMOS RAM can be set to specific values or cleared to the system
default values using the BIOS SETUP program. Also to prevent a lock-up
situation the CMOS RAM values can be cleared to the system defaults by
using the CLR CMOS jumper on the PWA.
2.9.7.
Non-volatile CMOS Memory Battery
An external coin-cell style battery provides power to the RTC and CMOS
memory when system power is removed. The battery has an estimated
lifetime of five to seven years and is socketed for easy replacement.
Reference: BT1
Socket Type: COIN TYPE
2.9.8.
IR (Infra-Red) Support
The IN440EX-D I/O subsystem incorporates an IR interface supporting the
following industry standards; Fast IR, IRDA (HP-SIR), ASK-IR. The IR
header provides the necessary signal interface allowing a two-way wireless
communication port using infrared as the transmission medium. The user
can transfer files to/from portable devices such as laptops, PDA’s and
printers using application software such as LapLink. The Fast IR
