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XRT94L33
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Rev.1.2.0.
9
PIN #
SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION
AF21
PDBEN_L
I
TTL
Bi-directional Data Bus Enable Input pin:
This input pin permits the user to either enable or tri-state the Bi-
Directional Data Bus pins (D[7:0]), as described below.
Setting this input pin “low” enables the Bi-directional Data bus.
Setting this input “high” tri-states the Bi-directional Data Bus.
AF20
PBLAST_L
I
TTL
Last Burst Transfer Indicator input pin:
If the Microprocessor Interface is operating in the Intel-I960
Mode,
then
this
input
pin
is
used to indicate
(to
the
Microprocessor Interface block) that the current data transfer is
the last data transfer within the current burst operation.
The Microprocessor should assert this input pin (by toggling it
“Low”) in order to denote that the current READ or WRITE
operation (within a BURST operation) is the last operation of this
BURST operation.
Note:
The user should connect this input pin to GND
whenever the Microprocessor Interface has been
configured to operate in the Intel-Async, Motorola 68K
and IBM PowerPC 403 modes.
AG22
PINT_L
O
CMOS
Interrupt Request Output:
This open-drain, active-low output signal will be asserted when
the Mapper/Framer device is requesting interrupt service from
the Microprocessor.
This output pin should typically be
connected to the “Interrupt Request” input of the Microprocessor.
AB24
RESET_L
I
TTL
Reset Input:
When this “active-low” signal is asserted, the XRT94L33 will be
asynchronously reset. When this occurs, all outputs will be “tri-
stated” and all on-chip registers will be reset to their “default”
values.
AE18
DIRECT_ADD_SEL
I
TTL
Address Location Select input pin:
This input pin must be pulled “HIGH” in order to permit normal
operation of the Microprocessor Interface.
SONET/SDH SERIAL LINE INTERFACE PINS
T3
RXLDAT_P
I
LVPECL
Receive STS-3/STM-1 Data – Positive Polarity PECL Input:
This input pin, along with RXLDAT_N functions as the
Recovered Data Input, from the Optical Transceiver or as the
Receive Data Input from the system back-plane
Note:
For APS (Automatic Protection Switching) purposes,
this input pin, along with “RXLDAT_N” functions as the
“Primary” STS-3/STM-1 Receive Data Input Port.