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Paradise P300 User Manual

Page 175

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P300H

P300 Series Modem Installation and Operating Handbook

Page 175

MIL-STD-188-114A INTERFACE

The P300 Series terrestrial interface is compliant with the interfaces defined in MIL-STD-188-114A when
set in RS422 mode.

This MIL-STD document specifies three types of `balanced generators`

Type 1

Low offset voltage, for <100kbps. Defined in this 1985 document for compatibility

with “older equipment”.

Type 2:

3V offset maximum, for 100kbps to 10Mbps. MIL-STD-188-114A actually

specifies this “corresponds to the EIA RS-422A balanced generators”

Type 3:

New terminated voltage generator for >10Mbps

Strictly the P300 Series is compliant with the Type 2 interface, defined for use from 100kbps to 10Mbps,
however in the P300 Series this interface will also operate down to 4800bps. The low offset voltage Type
1 generator is not supported, but as specified for use with “older equipment” in 1985, should not be an issue
today. The Type 3 is for data rates beyond the P300 Series operating range, and also is not supported.

A few notes from MIL-STD-188-114A

“Connectors, pin assignments and communication protocols are not standardised in this MIL-STD

document”

FED-STD-1030A may be considered equivalent to EIA RS423A and CCITT V.10
FED-STD-1020A may be considered equivalent to EIA RS422A and CCITT V.11