User manual

Chapter 2. Port Card Overview
2-4 FMUX-01Mar 2003
When the MULTIPLEXER UNIT is ordered with an RS449 Port Card option, a 4-
CHANNEL RS-449 Card and adapter cable are supplied with each DB37 wired according
to the following table.
SIGNAL
FUNCTION
DB37
PIN
RS-449
CIRCUIT
Direction DESCRIPTION
Protective
Ground
1 Frame ?
Chassis ground.
May be isolated from signal ground.
Signal
Ground
19,20,
37
SG,RC,
SC
? Common signal ground.
Transmitted
Data
4
22
SD(A)
SD(B)
To MUX
UNIT
Serial digital data from DTE.
Received
Data
6
24
RD(A)
RD(B)
Fm. MUX
UNIT
Serial digital data at the output of the
MULTIPLEXER UNIT receiver.
Request to
Sent
7
25
RS(A)
RS(B)
To MUX
UNIT
A ON signal to the MULTIPLEXER UNIT when
data transmission is desired.
Clear to
Sent
9
27
CS(A)
CS(B)
Fm. MUX
UNIT
Constantly ON.
Data Set
Ready
11
29
DM(A)
DM(B)
Fm. MUX
UNIT
Constantly ON,
Except during test loops.
Data Terminal
Ready
12
30
TR(A)
TR(B)
To MUX
UNIT
DTR not used, used for a received serial data rate
clock input from the DTE.
Data Carrier
Detect
13
31
RR(A)
RR(B)
Fm. MUX
UNIT
Constantly ON, except when a loss of the received
carrier signal is detected.
External
Transmit clock
17
35
TT(A)
TT(B)
To MUX
UNIT
A transmitted data rate clock input from the data
source.
Transmit
Clock
5
23
ST(A)
ST(B)
Fm. MUX
UNIT
A transmitted data rate clock for use by an
external data source.
Receive
Clock
8
26
RT(A)
RT(B)
Fm. MUX
UNIT
A received data rate clock for use by an external
data source.
Remote
Loop back
14 RL
To MUX
UNIT
When on, commands MULTIPLEXER UNIT into
remote loop back.
Local
Loop back
10 LL
To MUX
UNIT
When on, commands MULTIPLEXER UNIT into
local loop back.
Test Indicator 18 TM
Fm. MUX
UNIT
ON during any test mode
Table 2-3 : DB37 adapter cable pin out for RS-449