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XRT94L33
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Rev.1.2.0.
31
C9
C10
A8
TxPOHFrame_0
TxPOHFrame_1
TxPOHFrame_2
O
CMOS
Transmit Path Overhead Input Port – Frame Output pin:
These
output
pins,
along
with
the
“TxPOH_n”,
“TxPOHEnable_n”,
“TxPOHIns_n”
and
“TxPOHClk_n”
function as the “Transmit Path Overhead Input Port”.
The exact function of these output pins depends upon whether
the user inserting POH or TOH data via the “TxPOH_n” input
pins.
If the user is only inserting POH data via these input pins:
The “TxPOH” port will pulse these output pins “high” whenever
it is ready to accept and process the J1 byte (e.g., the very first
POH byte) via this port.
Notes:
1.
The externally circuitry can determine whether the
“TxPOH” port is expecting the A1 byte or the J1 byte, by
checking the state of the corresponding “TxPOHEnable”
output pin. If the “TxPOHEnable_n” output pin is “LOW”
while the “TxPOHFrame_n” output pin is “HIGH”, then the
“TxPOH” port is ready to process the A1 (TOH) bytes.
2.
If the “TxPOHEnable_n” output pin is “HIGH” while the
“TxPOHFrame_n” output pin is “HIGH”, then the “TxPOH”
port is ready to process the J1 (POH) bytes.
D10
E11
C11
TxPOHIns_0
TxPOHIns_1
TxPOHIns_2
I
TTL
Transmit Path Overhead Input Port – Insert Enable Input
pin:
These input pins, along with “TxPOH_n”, “TxPOHEnable_n”,
“TxPOHFrame_n” and “TxPOHClk_n” function as the Transmit
Path Overhead (TxPOH) Input Port.
These input pins permit the user to enable or disable the
“TxPOH” input port.
If these input pins are pulled “high”, then the “TxPOH” port will
sample and latch data via the corresponding “TxPOH” input
pins, upon the falling edge of “TxPOHClk_n”.
Conversely, if these input pins are pulled “l(fā)ow”, then the
“TxPOH” port will NOT sample and latch data via the
corresponding “TxPOH” input pins.
Note:
If the “TxPOHIns_n” input pin is pulled “LOW”, this
setting will be overridden if the user has configured
the “Transmit SONET/STS-1 POH Processor” or
“Transmit STS-1 TOH Processor” blocks to accept
certain POH or TOH overhead bytes via the external
port.
B7
B9
B10
TxPOHEnable_0
TxPOHEnable_1
TxPOHEnable_2
O
CMOS
Transmit Path Overhead Input Port – POH Indicator
Output pin:
These output pins, along with “TxPOH_n”, “TxPOHIns_n”,
“TxPOHFrame_n”
and
“TxPOHClk_n”
function
as
the
“Transmit Path Overhead (TxPOH) Input Port”.
These output pins will pulse “high” anytime the “TxPOH” port is
ready to accept and process POH bytes.
These output pins
will be “l(fā)ow” at all other times.
TRANSMIT LINE/ SYSTEM SIDE INTERFACE PINS