Zhone IMACS 8000, User Manual

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4-8 Reference Guide
Model No.
Running Head
Data Modules and Applications Applications
4.3 Data Modules and Applications
This Integrated Access System supports multiple user cards for transport of digital data.
4.3.1 HSU Cards
The HSU card allows the connection of high speed data terminal equipment (DTE) and data
communications equipment (DCE) to WAN links, server cards (ADPCM) or another HSU
card. The HSU card also provides low or mid-density connectivity for local, synchronous
peripherals such as, LAN Bridge/Routers and legacy SNA/SDLC devices. Additionally, these
high speed data cards also provide broadcast functionality for point to multi-point operation
suitable for applications such as video conferencing. When used in conjunction with an 8840
PRI Server Card, the HSU card can be used to provide switched data application functionality.
(i.e. telephone call centers). All HSU cards can be installed in any of the User Slots in an
Integrated Access System chassis.
The various models of the HSU Card are as follows:
• The 8000-HSU-2P-V11 (820360) Trunk Card supports two V.11/X.21 data ports The
ports may be configured as user ports, or can be used as externally clocked network
interface ports.
• The 8000-HSU-2P (821260) HSU card supports two “true” V.35 synchronous data ports.
• The 8000-HSU-4P (821570) HSU card provides four ports which can be individually
configured to support RS530, RS449/422, and V.35. devices.
Each port on a HSU can be independently configured to operate at speeds of Nx56 or Nx64
Kbps, where N equals 1 to 24 in T1 mode or 1 to 31 in E1 mode. In addition to the data rate,
each synchronous port’s Transmit Clock can be programmed for Internal or External modes
and both the Clock and Data Polarity may be inverted through software.
The External Transmit Clock mode and the Inverted Clock Polarity mode may be useful in
ensuring that both the Transmit Clock and the Transmit Data are in sync when they reach the
HSU port.
This should occur when the HSU port and the attached device are connected over a long cable.
The Data Polarity may be inverted to ensure the density for Nx64 Kbps data circuits
supporting HDLC-based protocols that are connected to non-B8ZS T1 facilities.
The “Clear To Send” control lead may always be set to high, low or local mode. In local mode,
the CTS signal reflects the state of the Request To Send (RTS) signal that is received from the
attached DTE device. In that mode, the delay between RTS and CTS is software set-able, with
options of 0, 30, 60 or 100 milliseconds. Additionally, if the HSU port is programmed to
operate at Nx56 Kbps, then RTS will be transmitted end-to-end and presented as RLSD at the
far end of the circuit.