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Preliminary Data Sheet, Rev. 1
October 2000
TMXF28155 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
101
Lucent Technologies Inc.
TMUX Functional Description
(continued)
Receive Direction (Receive Path from Sonet/SDH)
(continued)
Sync Status Monitor
The S1 byte is allocated for synchronization status. S1 bits [7:4] are used to convey a 4-bit code of which only six
patterns are defined with the remaining codes reserved for quality levels defined by individual administrations.
The S1 byte can be monitored in two modes: (1) as an entire 8-bit word or (2) as one 4-bit nibble (bits [7:4]) as pro-
grammed by TMUX_S1MODE4 (Table 57).
1. TMUX_S1MODE4 = 0 the associated state, delta, and mask registers are TMUX_RS1MON[7:0] (Table 65),
TMUX_RS1MOND (Table 44), and TMUX_RS1MONM (Table 48), respectively.
2. TMUX_S1MODE4 = 1 the associated state, delta, and mask registers are TMUX_RS1MON[7:4],
TMUX_RS1MOND, and TMUX_RS1MONM.
A new value will be detected after a programmed number of consecutive occurrences of a consistent new value in
the incoming S1 Byte as determine by the value in TMUX_CNTDS1[3:0] (Table 60). A maskable event
TMUX_RS1BABE (Table 44), is set if a programmed number of consecutive frames pass without a validated mes-
sage occurring as determined by the value in TMUX_CNTDS1FRAME[3:0] (Table 60). In 8-bit mode, the entire
value is monitored for an inconsistent value; while in 4-bit mode, only the most significant nibble is monitored for an
inconsistent value. This continuous N times detection counter will be reset to 0 upon the transition of the framer
into the out-of-frame state.
Receive Transport Overhead Access Channel (RTOAC)
A transport overhead access channel (TOAC) is provided on-chip to drop the transport overhead (TOH) portion of
the incoming SDH or SONET frame.The TOAC channel supports three modes of operation based on the configu-
ration of TMUX_RTOAC_D13MODE (Table 79) and TMUX_RTOAC_D412MODE (Table 79).
The TOAC channel consists of the following signals:
I
A clock signal sourced by the device pin, RTOACCLK (external output pin AD1). The clock frequency depends
on the values of TMUX_RTOAC_D13MODE and TMUX_RTOAC_D412MODE. See Table 25 below.
I
A data signal out of RTOACDATA (external output pin AD3). The data rate and the values transmitted depend on
the values of TMUX_RTOAC_D13MODE and TMUX_RTOAC_D412MODE. See Table 25 below.
I
An 8 kHz synchronization signal, out to output pin, RTOACSYNC (external output pin AA5). The sync signal is
normally low. During the last clock period of each frame coincident with the least significant bit of the last byte
(the eighty-first byte for all TOH modes), the sync signal is driven high.
Table 25. Receive TOAC Modes
TOAC Mode
TMUX_RTOAC_D13
Mode Value
1
0
0
TMUX_RTOAC_D412
Mode Value
X
1
0
Number of Data Bytes
per Frame
3
9
81
Clock Rate
DCC1—DCC3
DCC4—DCC12
Full TOH Mode
192 KHz
576 KHz
5.184 MHz