TMXF28155/51 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
Preliminary Data Sheet
May 2001
392
Agere Systems Inc.
17 TMUX Functional Description
(continued)
The TTOAC channel consists of the following signals:
I
A data signal received by the TMUX in the transmit direction (TTOACDATA, pin AE2). The data bytes per frame
received depend on the values of TMUX_TTOAC_D13MODE and TMUX_TTOAC_D412MODE. See
Table 533
below.
I
A clock signal sourced by the TMUX (TTOACCLK, pin AB6). The clock frequency depends on the values of
TMUX_TTOAC_D13MODE and TMUX_TTOAC_D412MODE. See
Table 533
below.
I
An 8 kHz synchronization signal (TTOACSYNC, pin AF3) is sourced by the TMUX. This sync signal is normally
low; during the last clock period of each frame, coincident with the least significant bit of the last byte, the sync
signal is high.
Table 533. Transmit TOAC Modes
Transmit TOAC
—
DCC1 through DCC3 Mode.
In this mode, DCC bytes 1 to 3 are received serially on the data
pin. The clock rate is 192 kHz. The data bytes are received MSB first, and the sequence of data bytes is DCC1,
DCC2, and DCC3. The data signal is partitioned into frames of 3 bytes. The frame repetition rate is 8 kHz.
Transmit TOAC
—
DCC4 through DCC12 Mode.
In this mode, DCC bytes 4 to 12 are received serially on the data
output. The clock rate is 576 kHz. The data bytes are received MSB first, and the sequence of data bytes is DCC4,
DCC5, DCC6, DCC7, DCC8, DCC9, DCC10, DCC11, and DCC12. The data signal is partitioned into frames of
9 bytes. The frame repetition rate is 8 kHz.
Transmit TOAC
—
Full TOH Access Mode.
In this mode, where TMUX_TTOAC_D13MODE = 0 and
TMUX_TTOAC_D412MODE = 0 (
Table 117 on page113
), the data signal (TTOACDATA, pin AE2) is partitioned
into frames of 81 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 648 bits of
the previous frame. The remaining 7 bits of this byte are not specified.
Bytes shown in
Table 534
summarize the access capabilities of the transmit TOAC. This table describes the possi-
ble bytes in the outgoing frame that can be provisioned from the values on the TOAC channel. There are additional
mode bits described in
Table 535
that must be programmed to allow insertion from the TOAC channel. Bytes indi-
cated in bold type below are not specified in the standard, but are available for insertion into the outgoing frame via
the register bit, TMUX_TTOAC_AVAIL (
Table 117
). An X in
Table 534
indicates bytes that are don
’
t cares; the val-
ues of these bytes in the outgoing transmit frame are not related to the values on the TTOAC channel.
Table 534. Transmit Transport Overhead Byte Full Access Mode
TOAC Mode
TMUX_TTOAC_
D13MODE Value
1
0
0
TMUX_TTOAC_
D412MODE Value
X
1
0
Data Bytes per
Frame
3
9
81
Clock Rate
DCC1
—
DCC3
DCC4
—
DCC12
Full TOH mode
192 kHz
576 kHz
5.184 MHz
OH Parity
X
D1
X
X
D4
D7
D10
S1
X
X
X
E1
D2
X
X
D5
D8
D11
Z2
X
X
X
F1
D3
X
X
D6
D9
D12
E2
X
X
B1-2
D1-2
X
X
D4-2
D7-2
D10-2
Z1-2
B1-3
D1-3
X
X
D4-3
D7-3
D10-3
Z1-3
E1-2
D2-2
X
K1-2
D5-2
D8-2
D11-2
Z2-2
E1-3
D2-3
X
K1-3
D5-3
D8-3
D11-3
X
F1-2
D3-2
X
K2-2
D6-2
D9-2
D12-2
E2-2
F1-3
D3-3
X
K2-3
D6-3
D9-3
D12-3
E2-3