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A rs-232d pinouts – CANOGA PERKINS 2240 Fiber Optic Modem User Manual

Page 43

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2240 Fiber Optic Modem

43

Data Set Ready (DSR) and Test Mode (TM) are local status leads and follow the functions
described in RS-232D. DSR typically indicates that the modem is ready to handle transmit
data. During loopbacks, the behavior of this signal is dependent on the position of the DSR
jumper (see description of DSR jumper). TM indicates that a loopback is active on one or
both modems.

Local Loopback (LL) and Remote Loopback (RL) are loopback control leads and perform
the same functions as the 2240 front panel LOOP switch LOC and REM positions. LL and
RL are interface signal inputs which can be used to activate the LOC or REM loop functions.

Table 4-A.

RS-232D

Pinouts

Pin

RS-232D

Direction

Number

Pin Name
(abbrev)

Full Name

1

PG

Protective Ground

-

2

TD

Transmit Data

to modem

3

RD

Receive Data

from modem

4

RTS

Request to Send

to modem

5

CTS

Clear to Send

from modem

6

DSR

DCE Ready

from modem

7

SG

Signal Ground

-

8

DCD

Receive Line Sig. Det.

from modem

12

SDCD

Secondary Line Sig. Det.

from modem

13

SCTS

Secondary CTS

from modem

14

STD

Secondary TD

to modem

15

SCT

Transmit Clock

from modem

16

SRD

Secondary RD

from modem

17

SCR

Receive Clock

from modem

18

LL

Local Loopback

to modem

19

SRTS

Secondary RTS

to modem

20

DTR

DTE Ready

to modem

21

RL

Remote Loopback

to modem

22

RI

Ring Indicator

from modem

23

DSRS

Data Signal Rate Selector

to modem

24

SCTE

Transmit Clock External

to modem

25

TM

Test Mode

from modem