Memory Configuration
VL-486-4 Reference Manual
Configuration – 23
CMOS RAM C
ONFIGURATION
The VL-486-4 CPU card is shipped with the battery disconnected. Since the battery provides
backup power to the CMOS RAM and the real time clock circuits when the card is powered
down, the battery must be activated before putting the card in service.
To activate the battery, move jumper V5 to position [2-3] (bottom position) as shown.
Jumper V5[1-2] (top position) can be briefly used to erase the contents of the CMOS RAM
should it become necessary to do so.
Table 8: CMOS RAM Jumpers
Jumper
Block
Description
As
Shipped
V5[1-2]
CMOS RAM Erase
In
— Erases CMOS RAM and Real Time Clock contents
Out
— Normal operation (V5[2-3] must be in)
In
V5[2-3]
CMOS RAM Power
In
— Connects power to CMOS RAM and Real Time Clock circuits
Out
— Power disconnected
Out
