TMXF28155 Datasheet, PDF (19/606 Pages) Agere Systems – TMXF28155 Super Mapper 155/51 Mbits/s SONET/SDH x28/x21 DS1/E1

Preliminary Data Sheet
May 2001
TMXF28155 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
3 Pin Information (continued)
Table 5. Telecom Bus (Low-speed I/O) Pin Description (continued)
Pin
Symbol
Type I/O
Description
AC3
TLSC52
—
I/O Transmit Low-speed Clock. When in output (master) mode,
it is the transmit side 51.84 MHz clock output synchronous to
transmit high-speed input clock. When in input mode, it
receives a 51.84 MHz clock input synchronous to transmit
high-speed input clock
Note: TLSCLK is used as the master clock for the T1/E1
framer and should therefore be provided even if the
TMUX SPE and VT mappers are not used.
AD2
TLSSYNC52
—
I/O Transmit Low-speed Sync. When in output (master) mode,
it is the transmit side frame sync output synchronous to
51.84 MHz output. When in input (slave) mode, it receives the
transmit side frame sync input synchronous to 51.84 MHz
input.
3.3.4 TOAC and POAC
The transport and path overhead access channels (TOAC and POAC) allow parts of the SONET/SDH overhead to
be examined externally (receive direction) or overwritten (transmit direction) through serial data ports. Each port
has clock and data lines and synchronization signal that marks the last bit of the frame so that the rest of the over-
head bytes can be identified.
The receive TOAC and POAC channels contain all of the respective overheads bytes. The transmit channels con-
tain space for all the overhead bytes, but whether they are actually transmitted depend on how the device is pro-
grammed. Some overhead bytes can not be modified; others may be modified only through the CPU port; some
may be modified only through the overhead access channels; and some may be modified either through the CPU
port, or through the overhead access channels.
Table 6. TOAC and POAC
Pin
Symbol
AD1
RTOACCLK
AD3
RTOACDATA
AA5
RTOACSYNC
AB6
TTOACCLK
AE2
TTOACDATA
AF3
TTOACSYNC
AE3
RPOACCLK
AD4
RPOACDATA
Type
I/O
Description
—
O Receive TOAC Clock. Receive side serial access channel
clock output for the transport overhead bytes.
—
O Receive TOAC Data. Receive side serial access channel
data output for the transport overhead bytes.
—
O Receive TOAC Synchronization. Receive side sync output
for TOAC channel. Active-high during the LSB of the last
byte.
—
O Transmit TOAC Clock. Transmit side serial access channel
clock output for the transport overhead bytes.
—
I
Transmit TOAC Data. Transmit side serial access channel
Pull down ^{data input for the transport overhead bytes.}
—
O Transmit TOAC Synchronization. Transmit side sync out-
put for TOAC channel. Active-high during the LSB of the last
byte.
Path Overhead Access Channel (POAC)
—
O Receive POAC Clock. Receive side serial access channel
clock output for the path overhead bytes.
—
O Receive POAC Data. Receive side serial access channel
data output for the path overhead bytes.
Agere Systems Inc.
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