BCM Advanced Research
49
Connector Type:
USB CONN, DUAL
Connector Part Number:
Molex, 87525-001 or equivalent
Table 2.21. USB-1 & 2 Connector Pinout
PIN
DESCRIPTION
COMMENT
1
VCC
Cable power
2
- Data
3
+ Data
4
Ground
Cable ground
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.
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
