Paradise P300 specifications P1440 in RS232 Mode, Shield

P1440 IN RS232 MODE

The P1440 is the standard interface supplied with the P300 Series Modem. If RS232 is selected under Change, Terr-Intfc, Electrical then the following interface description applies.

Min	Signal Description	RS232
Req		Name
DATA CIRCUIT TOWARDS MODEM (TX)
	Clock In	DA
U	Data In	BA
	Sig’ Valid In	CA
	Sig Accpt’d Out	CB
	Int’ Tx Clock Out	DB
DATA CIRCUIT FROM MODEM (RX)
	Clock Out	DD
	Data Out	BB
	Sig’ Valid Out	CF
COMMON LINES
	Signal Ground	AB
U	Shield/Protective ground	SHIELD
	Device (DTE) Ready In	CD
	Device (DCE) Ready Out	CC
	Local Loop In	LL
	Remote Loop In	RL

Circuit Number

113

103

105

106

114

115

104

109

102

101

108

107

141

140

25 pin			37 pin			Electrical
A		B	A		B	Levels
	24			17		RS232
	2			4		RS232
	4			7		RS232
	5			9		RS232
	15			5		RS232
	17			8		RS232
	3			6		RS232
	8			13		RS232
	7		19, 20, 21			Ground
	1			1		Screen
	20			12		RS232
	6			11		RS232
	18			10		RS232
	21			14		RS232

The maximum data rate is 100kbps (over good quality 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 50kbps to 20m, 25kbps to 40m etc). NOTE this is a synchronous RS232 interface, if you need an asynchronous interface, please contact the factory.

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. The EIA530 connector is pin compatible with the standard 25 pin RS232 interface.

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 (CA) or `Device (DTE) Ready In` line (CD) 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 (CA) by selecting

Change, Tx, Modulator, Carrier, RTS-Controlled.

P300H P300 Series Modem Installation and Operating Handbook Page 170