P1440 In V.35 Mode - Paradise Datacom P300 Series Installation & Operating Handbook

P1440 IN V.35 MODE

The P1440 is the standard interface supplied with the P300 Series Modem. If V.35 is selected under
Change, Terr-Intfc, Electrical then the following interface description applies.
Min
Signal Description
Req
DATA CIRCUIT TOWARDS MODEM (TX)
Clock In
U
Data In
U
Sig' Valid In
Sig Accpt'd Out
Int' Tx Clock Out
DATA CIRCUIT FROM MODEM (RX)
Clock Out
U
Data Out
U
Sig' Valid Out
COMMON LINES
Signal Ground
U
Shield/Protective ground
U
Device (DTE) Ready In
Device (DCE) Ready Out
Local Loop In
Remote Loop In
The maximum data rate is 10Mbps (over good quality twisted pair screened cable), but this rate is reduced
as the connecting cables extend beyond 10m. As an estimate, assume the maximum rate halves as the
distance doubles (ie 5Mbps to 20m, 2.5Mbps to 40m etc).
The input clock/data phase is selected automatically, reporting a `Data Marginal` warning whenever it
has to switch phase. If the modem reports Data Marginal frequently then this is not a modem fault but an
indication that you have a clocking problem external to the modem (ie changing clock/data phase, a
problem which would otherwise have caused untraceable data errors). With the Tx Clocking Set to Tx
Clock In the `Data In` signal is checked against the `Clock In` signal. With the Tx Clocking Set to Internal
or Rx the `Data In` signal is checked against the `Int' Tx Clk Out` signal.
Note that although there are both 25 pin EIA530 pinout and 37 pin RS449 pinout connectors on the rear
panel, these are simply connected in parallel. Do not use both connectors at the same time. If you
require the older 34 pin `Winchester` connector then an adaptor lead is required, please contact the factory
for details.
By selecting Change, Terr-Intfc, Control Lines it is possible to configure the modem to raise an alarm if
either the `Sig' Valid In` line (RTS) or `Device (DTE) Ready In` line (DTR) switch to the inactive state. It is
also possible to configure the Tx carrier to be switched on and off by the `Sig' Valid In` line (RTS) by
selecting Change, Tx, Modulator, Carrier, RTS-Controlled.
P300H P300 Series Modem Installation and Operating Handbook
V.35 Circuit
Name Number
A
SCTE 113 24
SD 103 2
RTS 105
CTS 106
SCT 114 15
SCR 115 17
RD 104 3
RLSD 109
SG 102
FG 101
DTR 108
DSR 107
LL 141
RL 140
25 pin 37 pin
B A B
11 17 35
14 4 22
4 7
5 9
12 5 23
9 8 26
16 6 24
8 13
7 19, 20, 21
1 1
20 12
6 11
18 10
21 14
Electrical Old Style
Levels Winchester
V.35 U & W
V.35 P & S
RS232 C
RS232 D
V.35 Y & aa
V.35 V & X
V.35 R & T
RS232 F
Ground B
Screen A
RS232 H
RS232
E
RS232 -
RS232 -
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