Remote Port User Interface; Protocol Structure; Protocol Wrapper - Radyne DMD2401 Operation Manual

Table of Contents

Advertisement

DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
1.Main Menu
2.Control Mode:Ft Panel
3.Remote Mode :RS-485
4.Remote Addr :32
6.Center Buffer
Buffer Fill%:49
-----------------UNIVERSAL G.703/SYNCHRONOUS INTERFACE CONTROLS-----------------
GENERAL
31.EXC Clock :10000000
32.Ref Source:Internal
33.Ext Ref Fq:10.000000
42.Tx Ckt ID :
43.Rx Ckt ID :
Enter Selection Number:
Figure 4-22. Closed Net/RS-422/V.35/RS-232 Interface Control Terminal Screen

4.4 Remote Port User Interface

The Remote Port of the DMD2401 allows for complete control and monitor functions via an
RS-485 or RS-232 Front Panel Configurable Serial Interface.
Control and status messages are conveyed between the DMD2401 and the subsidiary modems
and the host computer using packetized message blocks in accordance with a proprietary
communications specification. This communication is handled by the Radyne Link Level Protocol
(RLLP), which serves as a protocol 'wrapper' for the M&C data.
Complete information on monitor and control software is contained in the following sections.

4.4.1 Protocol Structure

The Communications Specification (COMMSPEC) defines the interaction of computer resident
Monitor and Control software used in satellite earth station equipment such as Modems,
Redundancy Switches, Multiplexers, and other ancillary support gear. Communication is bi-
directional, and is normally established on one or more full-duplex 9600-baud multi-drop control
buses that conform to EIA Standard RS-485. If a single device is placed on a single control bus,
then the control bus may conform to EIA Standard RS-232.
Each piece of earth station equipment on a control bus has a unique physical address, which is
assigned during station setup/configuration or prior to shipment. Valid decimal addresses on one
control bus range from 032 to 255 for a total of up to 224 devices per bus. Address 255 of each
control bus is usually reserved for the M&C computer.

4.4.2 Protocol Wrapper

The Radyne COMMSPEC is byte-oriented, with the Least Significant Bit (LSB) issued first. Each
data byte is conveyed as mark/space information with one mark comprising the stop data. When
the last byte of data is transmitted, a hold comprises one steady mark (the last stop bit). To begin
or resume data transfer, a space (00h) substitutes this mark. This handling scheme is controlled
by the hardware and is transparent to the user. A pictorial representation of the data and its
surrounding overhead may be shown as follows:
TM065 - Rev. 3.3
IF Input (dBm) :-54 [1.6 V]
Eb/No
:NO SYNC
Uncorrected SER:NO SYNC
Corrected
BER:NO SYNC
Offset Frq (Hz):+24997
2047 Error Cnt :NO SYNC
2047 BER
:NO SYNC
TX SETUP
51.Tx Terr Intf:RS-422
52.Tx Clock Sel:SCTE(Ext)
53.Tx Clock Pol:Auto
54.SCT Source
:Internal
55.Tx Framing
:None
User Interfaces
SW:F04780-- Ver:.2
Intf Pres :IDR V.35/422
+5
V Mon :+4.8
+12 V Mon :+12.5
-12 V Mon :-12.1
Events
:37
RX SETUP
71.Rx Terr Intf:RS-422
72.Buffer/msec :32
73.BufClk Sel
:RX SAT
74.Buff Clk Pol:Normal
75.Rx Framing
:None
4-35

Advertisement

Table of Contents
loading

Table of Contents