Installation
2-4
V.3600
Table 2-1. Pin Signal Descriptions
Pin
EIA-
232D
CCITT
V.24
Signal
Description
1
101
Shield
No connection
2
BA
103
Transmit-
ted Data
Serial digital data (to be modulated)
from a data terminal or other digital
data source: Synchronous data must be
accompanied by the modem transmit
clock (pin 15) or by an external data
rate clock (pin 24). Data transitions
should occur on positive-going clock
transitions; asynchronous data does not
require a transmit clock.
3
BB
104
Received
Data
Serial digital data output to the DTE
interface: Sync data is accompanied by
an internal data rate (receive) clock
(pin 17) that has positive-going
transitions on the data transition. Async
data does not require a receive clock.
4
CA
105
Request to
Send
A positive level to the modem when
data transmission is desired
5
CB
106
Clear to
Send
A positive level from the modem in
response to Request to Send and when
the modem is ready to transmit. *
6
CC
107
Data Set
Ready
A positive level from the modem when
power is on and ready to operate: In
dial-up operation, the modem must be
off hook to give a high DSR signal.*
7
AB
102
Signal
Ground
Signal or common signal and dc power
ground. **
8
CF
109
Received
Line
Signal
Detector
A positive level from the modem
indicating the presence of a received
signal (carrier detect). *
9
--
+12 Volts
+12 voltage reference
10
--
-12 Volts
-12 voltage reference
* 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.
