
XRT79L71
PRELIMINARY
9
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
1.1.11
The Receive SSM Controller Block (E3, ITU-T G.832 Applications Only)
The purpose of the Receive SSM Controller Block is to permit a given terminal equipment to receive (and
extract out) the SSM (Synchronization Status Message) from the remote terminal equipment, via the MA byte,
within each inbound E3, ITU-T G.832 frame.
1.1.12
The Receive Trail-Trace Message Controller Block (E3, ITU-T G.832 Applications Only)
The purpose of the Receive Trail-Trace Message Controller block is to permit a given terminal equipment to
receive (and extract out) the Trail-Trace Message from the remote terminal equipment, via the TR byte, within
each inbound E3, ITU-T G.832 frame.
1.1.13
The Receive FEAC Controller Block (DS3 Applications Only)
The purpose of the Receive FEAC Controller block is to permit the user to receive FEAC (Far-End Alarm &
Control) Messages from the remote terminal equipment.
NOTE: The Receive FEAC Controller Block is only active if the XRT79L71 is configured to operate in the DS3, C-bit Parity
Framing format.
1.1.14
The Receive LAPD Controller Block
The purpose of the Receive LAPD Controller block is to permit the user to receive LAPD/PMDL (Path
Maintenance Data Link) Messages from the remote terminal equipment. The Receive LAPD Controller block
comes with a Receive LAPD Controller and 90 bytes of on-chip RAM (for storage of inbound PMDL Messages)
after reception.
1.1.15
The Receive Payload Data Output Interface Block
The purpose of the Receive Payload Data Output Interface block is to output payload data (within the incoming
DS3 or E3 data-stream) via either a Serial or Nibble-Parallel interface, and to route this data to the off-chip
System-Side Terminal Equipment.
1.1.16
The Receive Overhead Data Output Interface Block
The purpose of the Receive Overhead Data Output Interface block is to permit the user to extract out the
overhead bits (within the incoming DS3/E3 data-stream) and to route this data to some off-chip System-Side
Terminal Equipment circuitry.
1.1.17
A more detailed Functional/Architectural Description of the XRT79L71 when configured to
operate
in
the
Clear
Channel
Controller
Mode,
is
in
this
document
(79L71_Arch_Descr_CC.pdf).
(Section 7.0- Architectural/Functional Description of the XRT79L71 1-Channel DS3/E3 ATM UNI/PPP/Clear-
Channel Framer with LIU IC - Clear Channel Applications).
1.2
BRIEF FUNCTIONAL ARCHITECTURE DESCRIPTION OF THE XRT79L71 - HIGH-SPEED HDLC
CONTROLLER OVER DS3/E3 MODE
If the XRT79L71 has been configured to operate in the High-Speed HDLC Controller over DS3/E3 Mode, then
it will have the Functional Architecture as is presented below in Figure 3.