tmxf28155 ETC-unknow, tmxf28155 Datasheet - Page 388

• Manufacturer Part Number: tmxf28155
• Description: Tmxf28155 Super Mapper 155/51 Mbits/s Sonet/sdh X28/x21 Ds1/e1
• Manufacturer: ETC-unknow

155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
17 TMUX Functional Description
The second section after the switch, the transport overhead section, is broken down into the following functional
parts:
All insert control functions that are inhibited will insert all zeros or all ones, depending on the value of microproces-
sor register bit, SMPR_OH_DEFLT
17.6.3 POAC Insert
One path overhead access channel (POAC) is provided on-chip to provision the path overhead (POH) portion of
the outgoing frame. The TMUX transmits up to three STS-1s. The register bits TMUX_TPOAC_SEL[1:0]
on page115
TMUX_TPOAC_SEL[1:0] = 00 designates no TMUX_TPOAC insertion, TMUX_TPOAC_SEL[1:0] = 01 designates
STS-1 #1, TMUX_TPOAC_SEL[1:0] = 10 designates STS-1 #2, and TMUX_TPOAC_SEL[1:0] = 11 designates
STS-1 #3.
A POAC channel consists of the following signals:
An 8 kHz synchronization signal (TPOACSYNC, pin AC5), sourced by the TMUX. The sync signal is normally low.
During the last clock period of each frame, coincident with the least significant bit of the eighth byte, the sync signal
is high.
The data signal is partitioned into frames of 9 bytes. The frame repetition rate is 8 kHz. Each byte consists of 8 bits
that are transmitted/received most significant bit first. The MSB of the first byte of each frame contains an odd/even
parity bit over the 72 bits of the previous frame. The remaining 7 bits of this byte are not specified. The B3, G1, and
H4 transmit path overhead bytes are not provisionable via the POAC channel.
Bytes shown in
care.
Table 530. Path Overhead Byte Access—Transmit Direction
388
A 576 kHz inverted clock signal sourced by the TMUX (TPOACCLK, pin AE4).
A 576 kbits/s serial data signal received by the TMUX in the transmit direction (TPOACDATA, pin AD5).
TOAC insert
Sync status byte (S1) insert
M0/M1—REI-L Insert
K1 and K2 insert
AIS-L insert
B2 calculation and insert
F1 byte insert
B1 generate and error insert
Scrambler
J0 insert control
A2 error insert
) designate which STS-1s POH is inserted from the transmit POAC channel.
POH Parity
Table 530
C2
J1
summarize the access capabilities of the transmit POAC channel. X indicates a don’t
(Table 67 on pag
(continued)
e68).
F2
X
X
K3
N1
F3
Agere Systems Inc.
May 2001
(Table 118