XRT75R12D_06 Datasheet, PDF (15/134 Pages) Exar Corporation – TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET

XRT75R12D
REV. 1.0.1 TWELVE CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
GENERAL CONTROL PINS
PIN #
SIGNAL NAME
TYPE
P3
TEST
****
AE25
TRST
I
AB23
TMS
I
AB5
TCK
I
AB4
TDI
I
AE2
TDO
O
DESCRIPTION
Factory Test Mode Input Pin
This pin must be connected to GND for normal operation.
NOTE: This input pin is internally pulled "Low".
Test Reset
Test Boundary Scan
Test Mode Select
Test Boundary Scan
Test Clock
Test Boundary Scan
Test Data Input
Test Boundary Scan
Test Data Output
Test Boundary Scan
MICROPROCESSOR PARALLEL INTERFACE -
PIN #
J26
SIGNAL NAME
Pmode
P24
PCLK
N24
CS
N22
WR
N23
RD
N25
RDY
TYPE
I
I
I
I
I
O
DESCRIPTION
This pin controls the Microprocessor Parallel Interface mode.
"High" sets a Synchronous clocked interface mode with a clock from the Host.
"Low" sets an Asynchronous mode where a clock internal to the XRT75R12D will
time the operations.
High speed clock supplied by the Host to provide timing in the Synchronous
Interface mode. This signal must be a square-wave.
Chip Select Input (active low)
Initiates a read or write operation. When "High", no parallel communication is
active between the LIU and the Host.
Write Input (active low)
Enables the Host to write data D[7:0] into the LIU register space at address
Addr[7:0].
Read Input (active low)
Commands the LIU to transfer the contents of a register specified by Addr[7:0] to
the Host.
Ready Line Output (active low)
Provides a handshake between the LIU and the Host that communicates when
an operation has been completed.
NOTE: This pin must be pulled "High" with a 3kΩ ± 1% resistor.
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