LG GDK-100 Manual page 92

GDK-100
DIGITAL KEY TELEPHONE SYSTEM
2. CON3, CON4: They are used to control the reference clock signal when multi-ISDN boards
are installed.
See [Clock Control Cable Wiring] in section 3.5.
The line connector and terminating resistors
Line No
Line 1
Line 2
Line 3
Line 4
!
Note
1. Two poles of SW2, SW3, SW4 and SW5 should be set to the ON position to terminate two
terminating resistors on a line. (default ON)
2. Terminating resistors and selectable switches are introduced only on PCB issue 3 or later,
but not on PCB issue 1 and 2. So if you use BRIB issue 1 and 2, the external terminating
resistors are required. For the external termination, you can get the terminating unit locally
or use GDK-162/100 TERM, which is the terminating unit with 4 P-to-P connections provided
by LGIC.
RJ45 type jack
CON8
CON7
CON6
CON5
SW1
LED1
LED2
LED3
LED4
CON2
CON4(OUT)
CON3(IN)
CON1
ON OFF
SW5
RJ45
CON8
ON OFF
SW4
RJ45
CON7
ON OFF
SW3
RJ45
CON6
ON OFF
RJ45
SW2
CON5
Figure 3.4.6.1
Terminating Resistors
Switch
SW5 terminating
SW4 terminating
SW3 terminating
terminating
SW2
GDK-100 BRIB
U11 U10
(ROM1) (ROM2)
BRIB Layout
83
All OFF
All ON
open
open
open
open