Amtelco infinity series, Техническое руководство

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The H.110 Bus & Clock Modes • 6-1 •
The H.110 Basic Rate ISDN Board
6.0 The H.110 Bus & Clock Modes
The Infinity Series H.110 Basic Rate ISDN Board provides a means of
connecting BRI B-channels to the digital H.110 computer telephony bus.
Through this bus, the B-channels can be connected to other H.110
compatible boards. To accomplish this, the board has complete access to
all streams and timeslots on the bus. It is capable of operating in a variety
of clock modes compatible with H.110 operation.
6.1 The H.110 Bus
The H.110 bus consists of 32 Pulse Code Modulation (PCM) streams
operating at an 8.192 MHZ. clock rate. Each stream contains 128
timeslots, for a total of 4096 timeslots. In addition to the PCM data signals,
there are a number of bit, frame, and network reference signals that are
used to synchronize the operation of multiple boards.
For the purposes of commands, a particular H.110 timeslot is referred to
by a four digit hexadecimal number. The first two digits are the stream
number, while the last two digits are the timeslot within the stream.
Streams range from 00h to 1Fh, and timeslots from 00-7Fh.
The physical H.110 bus is a backplane connection using the J4/P4
connector. The H.110 specification defines allowable impedance and signal
lengths on each board so that additional bus termination is not needed to
insure the proper operation of the bus. The maximum length of the bus
(24.8 in.) and the maximum number of slots (21) are also specified.
Different length pins are also used on the various connectors. This is done
so that the various signals are staged in the correct order.