Black Box 3600 Manual De Usuario
Installation
2-6
Modem 3600
Telephone Line Connection
The modem operates in these line-related modes:
• Dial
• Leased
• Leased
20
CD
108.2
Data
Termi-
nal
Ready
Termi-
nal
Ready
This circuit is positive when the
DTE is ready to originate or
answer a call in dial-up operation.
DTR must always be active (high)
in 2-wire private line operation.
Cycling DTR causes retraining.*
DTE is ready to originate or
answer a call in dial-up operation.
DTR must always be active (high)
in 2-wire private line operation.
Cycling DTR causes retraining.*
21
--
140
Remote
Digital
Loop-
back
Digital
Loop-
back
A positive level causes a digital
loopback test mode at the remote
modem.*
loopback test mode at the remote
modem.*
22
CE
125
Ring
Indicator
Indicator
In direct dial operation this circuit
is positive in response to an
incoming ring signal.*
is positive in response to an
incoming ring signal.*
23
CH
111
Data
Rate
Select
Rate
Select
Supplies a data rate control input
to select primary or fallback data
rate: Negative voltage selects
primary data rate and positive
voltage selects fallback data rate.*
to select primary or fallback data
rate: Negative voltage selects
primary data rate and positive
voltage selects fallback data rate.*
24
DA
113
External
Trans-
mit
Clock
Trans-
mit
Clock
A serial data rate clock input from
the data source. Positive clock
transitions correspond to data
transitions.
the data source. Positive clock
transitions correspond to data
transitions.
25
--
142
Test
Mode
Mode
Indicates the modem is in a test
mode.
mode.
Table 2-1. Pin Signal Descriptions (Continued)
Pin
EIA-
232D
232D
CCITT
V.24
V.24
Signal
Description
*
* Modem options may force these signals on or cause them to be ignored.
*
** Refer to Appendix C, Hardware Options.
*
† This function can be disabled or its logic sense reversed by hardware straps.