SAMSUNG
DCS-816
Installation Manual
7-6
7.7 Remote Programming (Figure 7-6)
To remotely program the system, connect a customer-provided modem to one of the serial inter-
face connectors (DB9) on an SIO option card (Figures 3-1 and 3-2), and to an unused SLT port.
Before connecting the modem, ensure that the system power is turned OFF. Any external
battery, if installed, should also be removed.
Otherwise, the system as well as the modem may
be severely damaged.
Use a pin-to-pin RS232C cable. Only pins 2, 3, 4, 5, 6, 7 and 8 are required. When the modem
needs to be more than 5 metres away from the system, shielded computer cable is required. Con-
nect a male DB9 connector to the SIO card and then connect a connector that meets the require-
ment of the modem to the other end. The cable must not exceed 100 metres.
7.8 Power Failure Transfer
If the system loses AC power and has no external battery, the two analogue trunk lines on the
base board are automatically switched to the last two stations.
1
st
Trunk line
to
Station 15 (SLT)
2
nd
Trunk line
to
Station 16 (SLT)
PIN CONNECTIONS TO MODEM
FIGURE 7-6
SIO BOARD (DTE DB9)
MODEM (DCE DB25)
RXD (2)
TXD (3)
GND (5)
DCD (1)
TXD (3)
RXD (2)
GND (7)
DCD (1)
THE SYSTEM POWER SHOULD BE REMOVED
BEFORE CONNECTING THE DEVICE
CONNECT A PC EQUIPPED WITH PCMMC TO
ONE OF THE DB9 CONNECTORS ON AN SIO
BOARD
RTS (7)
CTS (4)
DTR (4)
DTR (20)
DSR (6)
DSR (6)
