
TMXF28155 Supermapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
Data Sheet
June 2002
380
Agere Systems Inc.
17 TMUX Functional Description
(continued)
Receive TOAC
—
OH Parity.
Even or odd parity can be inserted into the first bit of the MSB byte of the TOAC out-
going frame by programming TMUX_RTOAC_OEPINS (
Table 127 on page 115
).
17.5.14 MSP 1 + 1 Payload Switch
The TMUX supports a payload 1 + 1 protection switch. In the receive direction, this occurs prior to pointer interpre-
tation. If TMUX_RPSMUXSEL1 = 1 (
Table 103 on page 96
), then the input receive data and clock are selected
from the protection path: device pins RPSD155P/N (pins AD10/AE10) and RPSC155P/N (pins AC10/AD11), rather
than from the normal (working) path device pins, RHSDP/N (pins AF7/AE7) and RHSCP/N (pins AC7/AD8).
17.5.15 Pointer Interpreter
The STS-3/STM-1 pointer interpreter logic block performs all necessary functions to support STS-3/STM-1, as well
as STS-1, pointer interpretation. The pointer interpreter operates as one machine in STM-1 mode and as three
independent machines in STS-3 mode. The following features are implemented:
I
The pointer interpreter consists of the following states:
— LOP: loss of pointer
— AIS: alarm indiction signal (all ones in H1 and H2)
— NDF: new data flag enabled (1001,0001,1101,1011, and 1000)
— NORM: normal (disabled NDF, normal pointer)
— INC: increment (inverted I bits)
— DEC: decrement (inverted D bits)
* This state diagram is based on the ETS-417-1-1 pointer interpretation state diagram (Figure B.1). Transitions of eight invalid pointers from the
INC, DEC, and NDF states into the LOP state have been added.
5-9007(F)
Figure 27. Pointer Interpretation State Diagram
NORM
DEC
INC
NDF
AIS
LOP
FROM ALL STATES
8 INVALID POINTERS*
8 INVALID POINTERS
FROM ALL STATES
3 AIS INDICATIONS
3 NEW POINTERS
INCREMENT
INDICATION
DECREMENT
INDICATION
8 NDF ENABLE
NDF ENABLE
NDF ENABLE
NDF
ENABLE
NDF
ENABLE
NDF
ENABLE
3 ANY
POINTERS
3 ANY
POINTERS
3 NEW POINTERS
3 NEW POINTERS
3 ANY POINTERS
3 NEW POINTERS
8 INVALID
POINTERS