
31
x r
PRELIMINARY
E3 UNI FOR ATM
XRT7234
REV. P1.0.0
77
117
TxOHIns
I
Transmit E3 Overhead Byte Serial Input Port Enable:
When the user
wishes to input his/her value for the overhead bytes into the outbound E3
data stream, he/she should assert this input pin. When this pin is “high”
then the TxOH Serial Input Port will become active, and will began sampling
the TxOH input pin upon the rising edge of TxOHClk signal. When this
pin is “l(fā)ow”, then the TxOH Serial Input Port will be disabled, and the
overhead bytes of the outbound E3 data stream will be internally generated.
118
NC
****
Not Bonded Out
78
119
TxOH
I
Transmit E3 Framer Overhead Bytes Serial Input Port input:
This
pin, along with the TxOHIns, TxOHMSB and TxOHClk pins comprise the
“Transmit E3 Framer OH Bytes” Serial Input Port. This input pin is active
when the TxOHIns input pin is “high”; and is disabled when TxOHIns is
“l(fā)ow”. When this input pin is active, it will sample the input signal on the
rising edge of the TxOHClk signal. The data that is received via this input
will be inserted into the Overhead bytes of the outbound E3 Frame (via
the Transmit E3 Framer Block)
120
TCellTxed
O
Transmit Cell Processor—Cell Transmitted Indicator:
This output pin
pulses “high” each time the Transmit Cell Processor transmits a cell to
the Transmit E3 Framer.
79
121
TxOHClk
O
Transmit E3 Framer Overhead Bit Serial Input Port—clock signal output.
This output clock signal, along with the TxOH, TxOHFrame, and TxO-
HIns pins, comprise the “Transmit E3 Framer OH Bytes” serial input port.
When this serial port is active, then the data applied to the TxOH input
pin will be into the serial port on the rising edge of this clock signal.
Note:
The TxOHClk signal is always active whether the “TxOH Serial Input”
port is active or not.
80
122
TxOHFrame
O
Transmit E3 Framer Overhead Bytes Serial Input Port—framing
signal indicator.
This output signal, along with the TxOH, TxOHClk and TxOHIns pins
comprise the “Transmit E3 Framer OH Bytes” serial input port. This output pin
pulses “high” when the value for the first “X” bit (in F-Frame #1) is expected
at the TxOH input pin.
Note:
This output pin is always active whether the “Transmit E3 Framer
OH Byte” Serial Input port is active or not.
PIN DESCRIPTION (CONTINUED)
Pin
No.
100 Pin Package
Pin No. 160
PinPackage
Symbol
Type
Description
PIN DESCRIPTION
(contd.)