microCOM — Instruct Ion

MicroCoM Communication System A ) Central Matrix Audie .

The MFZD Matrix frames of the MicroCOM system form the modular building blocks, each containing up to 24 M724B Matrix Amplifiers _ AlI 24 balanced inputs of the M724B modules are bused together on printed circuit backplane assembly , which terminates on connectors at the rear of the MFZD frame. Each M724B Matrix Amplifier contains twenty-four solid state CMOS crosspoints, followed by an output amplifier_ This module al lows the selections of any or all of the 24 Iine level inputs to be assigned and mixed to one common output. direct input on the M724B matrix amplifier is provided for expand- ing communication buses beyond 24 inputs The outputs from success- ive matrix blocks are mixed to the inputs of primary matrix block The crosspoints are activated by the control system via an X-Y co-ordinate type select philosophy This control is derived from the M771 Matrix Latch Module. See the sect ion "Central Matrix Control" for further details on the operation of the crosspoints. The audio inputs of the central matrix may be wired to jackfield to provide patching facilities. From this point they connect to the M770 Quad Buffer Amplifier Modules which provide isolation between the matrix and the incoming sources. These Buffer Amplifiers are housed in MFZDL mounting frame. AII terminations to this frame are on connectors similar to the MFZD ma trix blocks. The M770 Buffer Amplifier provides either bridging or matched load to the input source Four isolated outputs are provided for optional inter-matrix distribution, Test select crosspoints are provided which permit the injection of test signal into any input bus This feature is utilized in the optional matrix monitor package outlined in following section. The outputs of the MFZD matrix blocks may be wired to jackfield or terminated directly at terminal blocks at the rear of the equipment racks_ Additionally, the outputs may be paralleled to an optional output monitor bus. 2-1

. -

WAAD-BECK Systems LTDS SYSTEMS

MicroCoM Communication System B ) Centra Matrix Control The control system of the MicroCOM consists of processor based Input and Output Controllers Transmit/Receive and Matrix Latch Modules series of micro- with associated MicroCoM systems up to 24 inputs and 24 outputs require one Input and one Output Controller Module. In larger systems every 24 inputs require one M774A Input Controller and every 24 outputs require one M776A Output Controller Systems matrix sizes of 200 200 and beyond can be configured in this fashion Each M774A Input Controller is associated with M772 Transmit/ Receive Module. The M772 sends commands to the communication termi- nals that are connected to its 24 balanced serial I/0 data ports and in turn receives their assignment and key data In systems with the calling tally feature this module also transmits the calling tally information back to the remote terminals . The M774A Input Controller directs the flow of data between the remote terminals and the M772 Transmit/Receive Module. This data is transfered serially in three blocks of eight between the M772 and the Input Controller It is then re-formated and sent to all other control lers upon the request of Master Controller This data transfer takes place on multiprocessor bus which connects to all controllers The Input Controllers transmit and receive data via this bus while the Output Controllers only receive the data . The data transfer on this bus is synchronized by an Output Controller that is assigned to be the Master . selector switch in the system allows the choice of any one of the Output Controllers to be Master This provides maximum of reliability since no one particular module is vital to overall system operation Since the system is divided into groups of 24 inputs and 24 outputs the failure of one module would only effect its own group without disturbing the remaining system. The M776A Output Controllers assimilate and re-configure the data received from the Input Controllers. The data is assembled into crosspoint bit pattern and then transfered to the respective M771 Matrix Latch Modules . The M771's in turn control the crosspoint clos_ ures in the central matrix with this bit pattern.

2-3

WAAD-BECK SYSTEMS LTD_ SYSTEMS

MicroCom Communication System M771 Matrix Latch Module is located in the first position of each MFZD matrix block . multi position frame selector switch on each M771 is set to decode its appropriate address, i.ej position for matrix inputs to 24 or position for inputs 25 to 48 etc The audio crosspoints of an MFZD matrix block are activated by an X-Y type control from the M771 The crosspoint bit pattern of given output bus is loaded into these crosspoint control Iatches _ The Bus Select Strobe of this bus is then activated, which in turn enables the control gates of the respective M724B Matrix Amplifier. This in turn refreshes the "memory capacitors" of the M724B which determine the crosspoint state. AMI 24 output buses are addressed in this fashion consecutively approximately every 150 milliseconds, with each bus select strobe being enabled for approximately 500 micro_ seconds Figure below illustrates the data transfer between modules of the MicroCom control system To 4771 Mtrix LATCHES METD_MATRIX_BLoCK K771 CROSSPOINT MtRIx

MicroCoM Communication System Since the crosspoint assignment data is received and continously updated from the remote communication termina Is, data retention in the matrix control system is not necessary in the case of power failure. Upon receovery from power failure the system controllers will au tomatically reset, cycle through self-diagnostic program and then re-start their normal program. The assignment data is then up-dated from the remote comm unication terminals Note that the communication terminals include power fail circuit which retains the assignment data up to half an hour in case of power failure. , 4: 3 ' . _^

MicrocoM Communication System C) Communication Terminals _ - .

broad Iine of Communication Terminals designed to interface with the central matrix, complement the WBS MicroCOM Communication System. These may be divided into two catagories, primary and secondary terminals. The primary termina Is, known as the M7800 and M7810 series, interface directly with the central matrix on three pairs of audio wires The secondary terminals, known as the M7820 and M7830 series, are slaved to the primary terminals and connect to the central matrix indirectly through the primary stations AII terminals are powered directly from the ac power Iine and contain complex amplifiers for microphone, speaker and headset operation; An auto evelling type preamplifier assures constant output level over wide range of input voice variations. Normal and an Overload LED indicator permit positive ca ibration of the front panel sensitivity control for each particular communication station. transmit tally LED indicates when an audio signal is leaving the terminal Sidetone is provided for headset operation, giving the operator positive feedback of his own voice. The audio section of these terminals further includes solid state crosspoints for talkback operation between the primary and associated secondary terminals The primary terminals contain microprocessor based control system which communicates with the central matrix directly on pair of audio wires. The bi-directional data transfer on this Iine is based on RS422 format. It contains all assignment and key data for the selection of crosspoints in the centra matrix. In systems with the calling tally feature the calling tally data is sent to the appro- priate terminal on this Iine. If the respective calling station is assigned to fixed key, LED tally above the key will indicate the incoming call_ If the calling station is not programmed to fixed key and it is not presently selected on an assignable key its cal ling code will appear flashing in the display window above the D (or R) key The call may then be answered by simply acti- vating this lever key The key data transmitted to the central matrix may originate from either fixed key or an assignable key The fixed keys are pre-programmed to certain receiving station (or output bus in the central matrix) Their code selection is contained in an EPROM and may be changed by re-programming or replacing this memory chip. 2-6

MicroCoM Communication System The assignable keys (A, B, C and D ) may be programmed to any valid recei ving station by entering its corresponding code number on the assignment keypad. seven-segment readout in the display window above the respective key will indicate the selected station code _ ^ : t should be noted that audio of all incoming calls to communicat- ion terminal will always be heard regardless of assignment or tally functions In addition to the normal operating voltages the M780 Power Supply which is utilized in the primary termina Is, also contains nickel cadmium battery with trickle charger This battery provides back-up power for the RAM memory of the terminal' s control system for up to half an hour in case of power failure, thus reta ining the selected assignment data.

The primary terminals are available: in two basic configurations, the M7800 ser jes, which contains most necessary operational controls on the front panel and the M7810 series, which includes all active circui try but is designed to operate with remote key, assignment, microphone and speaker panels. The M7800 series of communication terminals are designed for appli- cations in video tape, telecine areas or locations where this rack mounted unit can be positioned within easy reach of the operator _ In studio facilities the M7810 offers the flexibility of permiting operational controls to be strategically located in consoles or similar equipment, while the unit itself may be mounted in nearby rack or in console pedestal Various configurations of desk mounted panels to complement the M7810 series of communication terminals are available, such as the M781 Rernote Assignment Module or the IKP series of intercom panels The secondary terminals of the M7820 and the M7830 series are designed to operate in conjunction with one or more of the primary terminals and are uti lized in applications such as telecine film islands or video tape production desks.

The audio circuitry of these units is similar of that of the primary terminals, but their inputs and outputs are connected to the associated primary terminals. Solid state crosspoints in the primary terminals prov ide signal paths to and from the central matrix. 2-7