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 multipoint Teleconference 
Control (TCA/B) task to processing the each task.  
7.23
When the teleconference condition has changed, such as the number of 
participating rooms and broadcasting location, the current teleconference  
condition is informed by the multipoint Teleconference Control (TCA/B) task, via 
the LAP-B Driver (LD) task, to all the participating terminals.  This information is 
superimposed on the monitor display in the respective rooms. 
						

							Page 70NECA 340-414-100 Revision 2.0
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 broadcasting 
style.
Broadcasting request SPR Terminal 
Õ MCUA terminal is allowed to broadcast the 
picture to all the terminals participating in 
the teleconference, when it has requested 
so.
Broadcasting indicates
SPI Terminal ¬ MCUThe notice of broadcasting terminal is 
send to all the terminals, participating in 
the teleconference.
Authorized picture receive 
requestRPR Terminal 
Õ MCUA terminal is allowed to receive the 
picture of a specific terminal,  when it has 
requested so.
Authorized picture receive 
indicateRPI Terminal ¬ MCUThe notice of receiving of the specific 
picture is broadcasted to all the terminals 
participating in the teleconference.
Talker detect control request VCR Terminal 
Õ MCUA terminal is allowed to turn ON/OFF its 
talker detection function, when it has 
requested so.
Talker detect control indicate VCI Terminal ¬ MCUThe notice of talker detection control is 
broadcasted to all the terminals 
participating in the teleconference.
Still picture transmission 
requestSSR Terminal 
Õ MCUA terminal is allowed to broadcast its 
stationary picture to all the terminals 
participating in the teleconference, when 
it has requested so.
Still picture transmission 
permissionSSC Terminal ¬ MCUThe notice of permission of transmitting 
the stationary picture is sent to only the 
requesting terminal.
Still picture transmission 
completeSSE Terminal 
Õ MCUAfter the MCU has received the 
completion notice of transmitting the 
stationary picture, it restores the previous 
teleconference conditions.
Teleconference terminal 
connection requestJNR Terminal 
Õ MCUA terminal is allowed to participate the 
designated group of the multipoint 
teleconference, when it has requested so.
Teleconference terminal 
connection indicatesJNI  Terminal ¬ MCUThe notice of the teleconference terminal 
connections broadcasted to all the 
terminals participating in the 
teleconference. 
						

							NECA 340-414-100 Revision 2.0Page 71
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 condition is 
sent to only the requesting terminal.
Asking request EQR Terminal 
Õ MCUIn the Tele-education mode, a receiving 
terminal requests a transmitting terminal 
to speak.  The receiving terminal can send 
a message with the speaking request.
Asking request indicates EQI Terminal 
¬ MCUThe notice of speaking request is 
broadcasted to all the terminals 
participating in the teleconference.
Asking request cancel ERC Terminal 
Õ MCUIn the Tele-education connection mode, a 
receiving terminal requests a transmitting 
terminal to cancel the speaking 
request.The receiving terminal can send a 
message with the speaking request cancel.
Asking request cancel 
indicatesECI Terminal ¬ MCUThe notice of the speaking request cancel 
is broadcasted to all the terminals 
participating in the teleconference.
Talking permission ETK Terminal 
Õ MCUA terminal is allowed/inhibited to speak 
and turns ON/OFF the voice signal input.
Talking permission indicates ETI Terminal ¬ MCUThe notice of speaking permission is 
broadcasted to all the terminal 
participating in the teleconference.
Switching monitor picture 
requestMPR Terminal 
Õ MCUThe broadcasting terminal is allowed to 
monitor a room other than currently 
monitored one.
Switching monitor picture 
indicatesMPI Terminal ¬ MCUThe notice of object monitoring change is 
broadcasted to all the terminal 
participating.
Status of teleconference 
terminal indicatesSTI Terminal ¬ MCUA terminal is allowed to expel from the 
designated group of the teleconference, 
when it has requested so.
The notice of the current teleconference 
connection is sent to all the terminals 
participating in the teleconference. 
						

							Page 72NECA 340-414-100 Revision 2.0
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 
whiteboardElectrical whiteboard data 
receiveBRCV Terminal 
Õ MCUA terminal transmits and receives the 
electrical whiteboard data.
Electrical whiteboard data 
transmissionBSND Terminal 
¬ MCUA terminal transmits and receives the 
electrical whiteboard data.
Remote 
station 
controlMove camera requestCAMS
Terminal 
Õ MCU 
Õ Te r m i n a lA local terminal requests the movement 
of camera in the conference room of 
remote station.
Camera status indicates CAMI Terminal ¬ MCU ¬ Terminal The notice of the camera state is sent to 
only the requesting terminal.
Remote station data receiveRRCV
Terminal 
Õ MCU 
Õ Terminal 
A terminal is allowed to transmit and 
receive the message from the designated 
terminal. Remote station data 
transmissionRSND Terminal ¬ MCU ¬ Terminal 
Talker name indicates CPNI Terminal ¬ MCU ¬ Te r m i n a lThe name of a speaker, who is going to 
speak in the conference room where the 
camera is pre-set, is sent to all the 
terminals participating in the 
teleconference. 
						

							NECA 340-414-100 Revision 2.0Page 73
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
03H = SLAVE CONSOLE CONTROL
10H = FOR CONTROL CAMERA OF REMOTE TERMINAL
14H = FOR ELECTRICAL WHITEBOARD DATA
OTHER = RESERVED 
						

							Page 74NECA 340-414-100 Revision 2.0
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 ROOMS.
COMMUNICATION TO TELECONFERENCE TERMINAL (TC5000)
COMMUNICATION TO CODEC (VL5000)
SPR (01)
[FPR]
[FPR]
[FUR]
SPI (02)
SPI (02)
SPI (02)SPI
INDICATION
SPI
INDICATION
SPI INDICATION
(a)  Broadcasting Request (Except Operator)
SWITCHING
MCU
TERMINAL1TERMINAL2
TERMINAL3
DEPRESS [2] 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 ROOMS. SPR (02)
[FPR]
[FPR]
[FUR]
SPI (02)
SPI (02)
SPI (02)SPI
INDICATION
SPI
INDICATION
SPI INDICATION
(b)  Broadcasting Request (Operator)
MCU
TERMINAL1TERMINAL2
TERMINAL3
DEPRESS [OPR] KEY ON REMOTE CONTROLLER
NOTIFY CHAIRMAN TO ROOM OPR (01)
OPI (01)
OPI (01)
OPI (01)OPI
INDICATION
OPI
INDICATION
OPI INDICATION
(c)  Operator Privilege Request 
						

							NECA 340-414-100 Revision 2.0Page 75
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 INDICATION
(d)  Authorized Picture Receive Request (Authorized Picture is Terminal3)
MCU
TERMINAL1TERMINAL2
TERMINAL3
DEPRESS [STILL SEND] KEY ON REMOTE CONTROLLER
STILL PICTURE SENDING NOTIFICATION IS RETURNED TO ORIGINAL REQUESTING TERMINAL
STILL PICTURE IS SENT TO ALL OF TERMINALS
SENT STILL PICTURE COMPLETION IS NOTIFIED TO MCU 5000A SSR (01)
[FPR]
[FUR]
SSE (01)
(f)  Still Picture Send Request
MCU
TERMINAL1TERMINAL2
TERMINAL3
DEPRESS [VOICE ACTIVATE] KEY ON REMOTE CONTROLLER
NOTIFY TERMINALS VCR (01)
VCI (01)
VCI (01)
VCI (01)VCI
INDICATION
VCI
INDICATION
VCI INDICATION
(e)  Talker Detect Control Request
MCU
TERMINAL1TERMINAL2
TERMINAL3
QUERY OPERATION STATE TO MCU 5000A
VERIFIED NOTIFICATION IS RETURNED TO ORIGINAL REQUESTING TERMINAL SRR (01)
SRC (01)
(g)  Status Read of teleconference Terminal Request 
						

							Page 76NECA 340-414-100 Revision 2.0
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 CONTROLLER
(h)  Tele-education Mode (1 of 2) 
						

							NECA 340-414-100 Revision 2.0Page 77
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 signal (internal or external) back on remote or local side.  The MCU 5000A 
can also generate pseudo noise pattern and carry out self-diagnostic test by  
checking the returned noise pattern.
CONSOLE (PC) MCU SPEAKER LISTENER1 LISTENER2
[TK ALW] [TK CNL]
ERC
ETI
ETIETI EQI
INDICATION
INDICATIONECI
ECI
ECI
ECI [TALKER CANCEL]
ETK
(h)  Tele-education Mode (2 of 2)
CONSOLE (PC) MCU (MASTER) TERMINAL M1 MSU SLAVE TERMINAL S1
REMOTE LOOP REQUEST RLCS (M1)
REQUEST
REQUEST
REMOTE LOOP
(i)  Remote Loop Setting
RLCS (S1)
RLCI (M1)
RLCI (S1)REQUEST RLI (S1)
RLI (S1) 
						

							Page 78NECA 340-414-100 Revision 2.0
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 as shown 
in Fig. 7-9.  Moreover, following functions to generate the test signal and check 
the looped back signal (loopback test) are available:
• Video signal loopback test
• Audio signal loopback test
• LSD loopback test
• Console loopback test
7.30Video signal loop test:  
The video signal loop test is carried out using the 
PN pattern generator/checker in the V SW/LSD IP unit.  The PN pattern from the 
PN pattern generator is looped back at the preset loopback point and inputted into 
the PN pattern checker, which checks the transmitted pattern with the received 
one.  When a line rate of 1.536 Mbps is selected for the loop test, the MUX strap 
in the EC H221 MUX unit must be set to OFF position.  The MCU software, the 
Video Switch I/O (PS) task, controls the video signal loop test
7.31Video signal loop test:  
The voice signal loop test is performed by using 
the test tone generation mode function of  the A CODEC unit.  The output level 
(0, -12, -24, -36 dBm0) and frequency (500, 800, 1000 and 1600 Hz) of test tone 
are selected.  The continuous output level of the test tone is measured, while the 
level of looped-back test tone is checked.  When the level measurement is selected 
as the test, the measured level value is indicated on the console display.  The MCU 
software, Voice Control I/O (VC) task, controls the voice signal loop test.
7.32LSD loop test (four 00H to 7FH data flames):  
The LSD loop test is done 
by the HSCX in the V SW/LSD IF unit.  The LSD from the HSCX is looped back  
at the preset loopback point and received by the HSCX.  The received LSD is 
checked with the transmitted LSD.  The MCU software, LAP-B Driver (LD) task 
controls the LSD loop test.
7.33Console loop test:  
The console loop test is carried out by the Serial 
Controller in the PG/SIO unit.  The  test loop is set automatically.  Two loopback 
points is selected:  one for the Serial Controller, the other for the control signal 
test, which is located  at the outside of RC-232C connector,  When the loopback 
point for control signal test is specified, a loop connector must be connected.  The 
MCU software, Console Drivers 1 and 2 (CD1 and CD2) control the console loop 
test.