NEC Mcu 5000a Multipoint Control Unit Equipment Manual

NECA 340-414-100 Revision 2.0Page 69
MCU 5000A Multipoint Control Unit General Description Manual
D: Teleconference 
Terminal 
Interface7.22
The control command is multiplexed in the picture data (called MLP) and 
transmitted from each conference  terminal.   At a receive terminal, this control  
command is extracted from the picture data and taken into the LAP-B Driver (LD) 
task, where it is analyzed.  Analyzed control command is transferred to the 
electrical Whiteboard Control (BCA/B) task or the...

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General Description Manual MCU 5000A Multipoint Control Unit
Command Details
7.24
Table 7-1 shows the detail command/response in this interface.
Table 7-1: Detail Command/Response (1 of 3)
TYPE DESCRIPTION COMMAND DIRECTION FUNCTION
Multipoint
controlOperator privilege request
OPR Terminal 
Õ MCUProvide operator privilege to request 
terminal.  
Operator privilege indication OPI Terminal ¬ MCUOperator privilege indication is sent to 
every entry terminal by...

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MCU 5000A Multipoint Control Unit General Description Manual
Table 7-1: Detail Command/Response (2 of 3)
TYPE DESCRIPTION COMMAND DIRECTION FUNCTION
Multipoint
controlStatus read of teleconference 
terminal requestSRR Terminal 
Õ MCUA terminal is allowed to receive the 
current condition of the designated 
teleconference group.  
Status read of teleconference 
terminal responseSRC Terminal ¬ MCUThe notice of receiving information on the 
designated teleconference...

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General Description Manual MCU 5000A Multipoint Control Unit
Table 7-1: Detail Command/Response (3 of 3)
TYPE DESCRIPTION COMMAND DIRECTION FUNCTION
Multipoint
controlRead site name indicates PDI Terminal 
Õ MCUThe MCU sends the terminal locations 
names to each terminals participating in 
the teleconference.
Message indicates MSD Terminal 
Õ MCUThe MCU requests each terminal 
participating in the teleconference to 
display the message.
Electrical...

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MCU 5000A Multipoint Control Unit General Description Manual
Interface Format
7.25
Fig. 7-7 shows the format of this interface.  Format of line are HDLC 
frame format.
Figure 7-7:   Command/Response Format
COMMAND RESPONSE
COMMAND CLASSIFICATION
COMMAND CODE
PARAMETER
(MAX. 254 BYTE)PARAMETER
(MAX. 254 BYTE) RESPONSE CLASSIFICATION
RESPONSE CODE +0
+1
+2+0
+1
+21 BYTE
1 BYTE
COMMAND/RESPONSE CLASSIFICATION: 01H = FOR MULTIPOINT CONTROL
02H = FOR CASCADE COMMUNICATION...

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General Description Manual MCU 5000A Multipoint Control Unit
Sequence Example
7.26
Fig. 7-8 shows the sequence example.  (Request from terminal 1.)
Figure 7-8:   Sequence Example (1 of 4)
SWITCHING
MCU
TERMINAL1TERMINAL2
TERMINAL3
DEPRESS [LOCAL SEND] KEY ON REMOTE CONTROLLER
PICTURE OF CONFERENCE ROOM EXCEPT ORIGINAL REQUESTING TERMINAL IS FREEZED.
PICTURE OF ORIGINATING CONFERENCE ROOM IS SET TO DISTRIBUTE ALL ROOMS
THE ORIGINATING TERMINAL IS NOTIFIED TO OTHER...

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MCU 5000A Multipoint Control Unit General Description Manual
Figure 7-8:  Sequence Example (2 of 4)
SWITCHING
MCU
TERMINAL1TERMINAL2
TERMINAL3
DEPRESS [SLCT RCV] KEY ON REMOTE CONTROLLER
PICTURE OF CONFERENCE ROOM EXCEPT ORIGINAL REQUESTING TERMINAL IS FREEZED.
PICTURE OF ORIGINATING CONFERENCE ROOM IS SWITCHED IN ALL DATA MODE.
RESPONSE TO ORIGINAL REQUESTING TERMINAL IS NOTIFIED RPR (03/01)
[FPR]
[FUR]
RPI (03/01)
RPI (03/01)
RPI (0)RPI
INDICATION
RPI
INDICATION
RPI...

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General Description Manual MCU 5000A Multipoint Control Unit
Figure 7-8:  Sequence Example (3 of 4)
CONSOLE (PC) MCU INSTRUCTOR CLASSROOM1 CLASSROOM2
[TALKER RQT] EQR
EQI
EQIEQI EQI
INDICATION
INDICATION
INDICATION
INDICATION
INDICATION
INDICATION
INDICATIONEQI
ECI
ETI
MPI
SPI
ETIEQR
EQI
ERC
ECIEQI
EQI
ECI
ECI [TALKER CANCEL][TALKER RQT]
[TK ALW]
[SITE SELECTION]
[INS/TK]
[START] ETK
ETI
MPR
MPI
SPR
SPI
ETK
ETI
ETI
ETI SPI
SPI MPI
MPI ETI
ETI
[ ] :  KEY ON THE MCU...

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MCU 5000A Multipoint Control Unit General Description Manual
Figure 7-8:  Sequence Example (4 of 4)
E: Loopback Test   7.27
Loopback tests are conducted to sectionalize the faulty units when a  
failure has occurred in the MCU 5000A.  Some of the loopback tests are carried  
out from the MCU console by inputting commands, and others are conducted by 
the switches mounted on the units.
7.28
The MCU 5000A has loopback points in each unit.  The MCU 5000A can 
loop a...

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General Description Manual MCU 5000A Multipoint Control Unit
F: MCU 5000A 
Loopback7.29
The MCU loopback has two functions; one is to generate the test signal 
and check the signal looped back inside of the equipment  (Local Loopback) is  
called the local side loop hereafter, the other is to loopback the external signal 
outside of the equipment (Remote Loopback) is called remote side loopback 
hereafter.  The local side and remote side loops are set at points A to H...