Home > GTE > Communications System > GTE Omni Si Database Technical Practices Issue 1 Manual

GTE Omni Si Database Technical Practices Issue 1 Manual

    Download as PDF Print this page Share this page

    Have a look at the manual GTE Omni Si Database Technical Practices Issue 1 Manual online for free. It’s possible to download the document as PDF or print. UserManuals.tech offer 3 GTE manuals and user’s guides for free. Share the user manual or guide on Facebook, Twitter or Google+.

    Page
    of 762
    							TL-130500-1001
    PDN
    Telenet\PEC
    bus
    \LPB
    \PCM
    bus
    Figure 32.2Synchronous Packet Manager Interface
    For an X.25 packet to be transmitted to the data system, it must
    be broken down into 1 l-byte packets, called mini-packets,
    which adhere to the MPP (Mini-Packet Protocol) format. For
    transmission from the PABX to the data network, mini-packets
    are stored (buffered) until a full X.25 packet is formed and then
    transmitted (see Figure 32.2).
    SW 5210Em7s-303 
    						
    							TL-130500-1001
    The SPM contains two 8-bit microprocessors, 80K of parity
    protected RAM, and 8K of ROM. The SPM contains the mini-packet receiver/transmitter and line driver circuits used to
    communicate with the PABX. The ROM in the SPM contains the
    programs necessary to boot the SPM from the PABX, a
    debugger, and limited hardware self-tests. The RAM in the
    SPM is provides the operational code needed to communicate
    with the data system, and is used for temporary storage, buffers,
    and operational parameters. The SPM performs packet
    assembler/disassembler functions and also contains the CRC
    (Cyclic Redundant Checking) error detect logic.
    The SPM contains the following switches and indicators:
    * SWITCH LIKK Indicator.This indicator shows whether the
    SPM is in a test condition or is receiving/transmitting 
    mini-packets.
    0 X.25 TEST ACTIVE Indicator. This indicator is off during
    normal operation.When the TEST pushbutton is depressed
    and diagnostic software is being downloaded from the system,
    this indicator will be on.
    l W25 TEST Pushbutton. This pushbutton is not operational for
    this version.
    r RESET Pushbutton. The RESET pushbutton causes a reset
    condition when depressed.
    @ DTE/DCE Switch. This two-position switch sets the SPM data
    communications mode of operation. When depressed, the
    SPM is in the DTE (Data Terminal Equipment) mode, allowing it
    to be connected to terminal equipment. When released, the
    SPM is in the DCE (Data Communication Equipment) mode,
    allowing it to be connected to transmission lines.
    s-304
    8187SVR 5210 
    						
    							TL-130500-1001DFP/APM (DIGITAL33.0 The DFP/APM provides voice communication as well as
    FEATUREPHONEthe interface between the asynchronous data equipment
    WITH APM)(terminals, personal computers, etc.) and the VPLC2 FB-17246
    card.
    The 
    DFP/APM interfaces with the voice system over the PEC and
    PCM buses and the data system over the LPB (Figure 33.1).
    Connection to the VPLC2 (FB-17246-A) card is over a single
    twisted pair. This connection supports both 
    IJoice and data
    communications. The DFP/APM is either locally or remotely
    powered over a separate twisted pair connection.
    Connection to the data device is provided by a standard 
    RS-232-CN.24 interface, located in the rear of the phone.
    Operating speeds of the data device can be 110. 300, 1200,
    2400, 4800, 9600 baud, and 19,200 bps.
    Contained within the 
    DFP/APM are the 8-bit microprocessor,
    memory, packet assembler/disassembler, transmit/receive
    buffers, the CRC (Cyclic Redundant Check) error detect logic.
    SVR 5210
    8187s-305 
    						
    							TL-130500-1001T+R
    O-
    Figure 33.1DFP/APM Voice and Data Bus Connection
    .
    7-
    T+R
    DFP/APM+1 
    FB-228[Tl\LPB
    ’
    DFP/APMTransmission33.1 Transmission of 11 -byte voice, data, and control
    information is sent as mixed mini-packets. The 11 -byte 
    mini-packets are transmitted at 128 Kbps in each direction. The
    effective throughput is 64 Kbps voice, 19.2 Kbps data and
    overhead= 128 Kbps in each direction.
    See Table 33.1 for feature comparisons of the APM, SPM, and
    DFP/APM. Tables 33.2 and 33.3 provide CCITTrecommendations and descriptions for the APM, SPM, and
    DFP:APM.S-306
    8/87SVR 5210 
    						
    							:TL-130500-1001
    DFPIAPM
    mini-packets
    dPLC2
    Figure 33.2Transmission from the Digital FeaturephonetotheSystem
    Simultaneous Voice33.2 The simultaneous voice and data structure is:
    Packetizingand Datal Data device log-on
    l Data call distinctive or simultaneous with voice call
    l Data characters briefly buffered at Digital Featurephone
    l Data characters packetized in 8-byte groups at Digital
    Featurephone
    l Preceded with two address bytes
    e Followed with one CRC error-checking byte
    l 11 bytes equal one mini-packet
    When the mini-packet arrives at the VPLC2 (Voice Packet Line
    Card) (Figure 
    33.2), it is given two extra bytes providing “from”
    information.
    SW 52108187s-307 
    						
    							TL-130500-1001
    digital bit stream
    voice and data packets
    CRC
    (control)address
    (control “to”)
    MPP 11 bitsNetwork
    Interface Card33.3 The NIC (Network Interface Card) bridges the LPB (Local
    Packet Bus) and the PCM (Pulse Code Modulation) bus. This
    provides data networking capabilities between systems across a
    Tl network interface. HDLC (Higher Data Level Control) conveys
    the data to/from the PCM bus while MPP (Mini-Packet Protocol)
    conveys data to/from the LPB (Figure 33.3).
    The NIC provides an X.25 communication link between a
    circuit-switched 
    Tl trunk line and a packet-switched
    async/sync data line. The card indirectly interfaces to an outside
    Tl line via internal circuit-switched connections on the PCM
    bus. True intergrated voice and packet-switched data
    networking capabilities are provided by this card (see Figure
    33.4).The 
    NIC’s responsibility is similiar to that of the SPM. However
    some major physical differences between the NIC and the SPM
    are:l The NIC occupies a complete slot space allowing it an ABI
    (Arbitrated Bus Interface) and a PCM interface
    l The NIC has 256K bytes of shared memory
    l The NIC has DMA (Direct Memory Access) hardware support,
    an associated new MPCC (Multiple Protocol Communication
    Control) chip, and a new interrupt control mechanism.
    8187SVR 5210 
    						
    							TL-130500-1001Table 33.1 Feature Comparison
    NOTES:* 1. For information on VPLC cards, see section 7.0.
    * 2. 
    SPMs can interface with an RS-232-C if speeds are below
    19.2 Kbps.
    * 3. Throughput will vary according to the PAD (Packet
    Assembler/Disassembler) parameter settings and data
    format.
    * 4. For speeds 
    > 9.6 Kbps up to 64 Kbps.
    axrmum distance from switch-3000 feetat
    ITT 
    V.35interface
    SW 52108187s-309 
    						
    							TL-130500-1001Table 33.1Feature Comparison (Continued)
    s-31 0cket Assembler/
    ontains CODECand other associated
    I  circuitry
    Table 33.2 CCITT Recommendations
    FEATURENOTE: X.28 is the language by which an X.3
    command is entered, converting 
    async. data
    into X.25 packets, thereby allowing the user to
    enter information through the 
    k:?yboard of the
    data device attached to the APM
    Interfaces externally to X.25 host or X.25
    PDNS (Telenet)
    8/‘87,
    X
    SW 5210 
    						
    							SW 52108187DEVICE
    3FP/APM
    EC-221 79-AAPM
    L
    I
    1I
    i
    c
    i
    EC-221 78-ASPM
    Type A
    EC-221 78-BSPM
    Type BTL-130500-1001
    Table 33.3
    DFP/AMP, APM, SPM Description
    FEATURE
    l Provides interface between asynchronous
    data equipment and the system
    l Receives and transmits W-232-C
    compatible signals, converting them into
    mini-packet protocol
    lCommunicates with the system over a
    single, twisted-wire pair
    lSupports speeds up to 19.2 Kbps
    l Provides interface between asynchronous
    data equipment and the system
    l Receives and transmit RS-232-C
    compatible signals, converting them into
    mini-packet protocol
    lCommunicates with the system over a
    single, twisted-wire pair
    lSupports speeds up to 19.2 Kbps
    lUsed for devices needing RS-232-C
    interface
    lSupports devices operating at speeds up
    to 19.2 Kbps
    lCommunicates with the system over a
    single, twisted-wire pair
    *Used for devices needing V.35 interface
    lSupports devices operating at speeds up
    to 64 Kbps
    eCommunicates with the system over a
    single, twisted-wire pair
    s-31 1 
    						
    							TL-130500-1001
    OMNI-SIPCM BusPD-200LPBCircuit
    Switched 
    -:;f-Packet
    Switched
    c-- Tl24 TlChannelst----- PD-200 -----i)Fiaure 33.4NIC Card within the 
    OMNI SI Svstem’s Architecture
    s-31 2
    -- -, - ---~- -_... -__-_._
    8187SVR 5210 
    						
    All GTE manuals Comments (0)

    Related Manuals for GTE Omni Si Database Technical Practices Issue 1 Manual