Metrodata DC3 00 Series, User Manual

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INSTALLATION & SET-UP
16
The tables below provide detailed timing definitions
Figure 3.5 DC3200 timing signal definitions
Figure 3.6 DC3000 timing signal definitions
3 . 1. 7 Line coding
Line coding is HDB3 (High-Density Binary 3). This setting is built into the unit and cannot be
altered. Therefore there is no bit-switch for ths item.
3 . 1. 8 Test Loop
This switch is used to initiate loop testing. Further detail is available in the next section.
Care should be taken when using loops, especially with TERM (Terminal) timing mode, as
invalid network clocking scenarios can be created.
Clocking mode Bit switch
position
E1 Transmit clock
source
V.35 Transmit timing V.35 Receive timing
INT
(Internal)
10
Derived from Internal
oscillator
CCT114
Transmit timing A / B
derived from internal
oscillator
CCT115
Receive timing A / B
derived from E1 line
received clock
LOOP (E1 line
receive)
00
Derived from E1 line
received clock
CCT114
Transmit timing A / B
derived from E1 line
received clock
CCT115
Receive timing A / B
derived from E1 line
received clock
TERM
(Terminal)
01
Derived from CCT 113
Terminal timing A / B
CCT 113
Terminal timing A / B
CCT115
Receive timing A / B
derived from E1 line
received clock
DTE Mode
11
Derived from CCT 113
Terminal timing A / B
CCT 113
Terminal timing A / B
CCT 113
Terminal timing A / B
Clocking
mode
Bit switch
position
E1 Transmit clock
source
X.21 Transmit timing X.21 Receive timing
INT
(Internal)
10
Derived from Internal
oscillator
CCT115
Signal timing A / B
derived from E1 line
received clock
CCT115
Signal timing A / B
derived from E1 line
received clock
LOOP (E1
line received)
00
Derived from E1 line
received clock
CCT115
Signal timing A / B
derived from E1 line
received clock
CCT115
Signal timing A / B
derived from E1 line
received clock
TERM
(Terminal)
01
Derived from CCT 113
DTE signal timing A / B
CCT 113
DTE signal timing A / B
CCT115
Signal timing A / B
derived from E1 line
recieved clock
DTE Mode
11
Derived from CCT 113
DTE signal timing A / B
CCT 113
DTE signal timing A / B
CCT 113
DTE signal timing A / B