XRT72L58 Datasheet, PDF (40/486 Pages) Exar Corporation – EIGHT CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

XRT72L58
EIGHT CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
REV. P1.1.2
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PRELIMINARY
PIN DESCRIPTION FOR THE XRT72L58
PIN #
T13
T14
T15
T16
T23
PIN NAME
GND
GND
VDD
VDD
CS
T24
Reset
T25
MOTO
T26
TestMode
U1
RxPOS[3]
U2
RxLineClk[3]
U3
TxInClk[3]
U4
RxNEG[4]
U23 RxOHEnable[3]/
RxHDLCDat5[3]
U24
RxOOF[3]
U25
NC
U26
RD_DS
V1
ExtLOS[3]
V2
TxInClk[4]
TYPE
****
****
****
****
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I
I
***
I
I
I
I
O
DESCRIPTION
Ground
Ground
Power Supply 3.3V + 5%
Power Supply 3.3V + 5%
Chip Select Input:
This active-low input signal selects the Microprocessor Interface Section of
the Framer and enables READ/WRITE operations between the Local Micro-
processor and the Framer on-chip registers and RAM locations.
Reset Input:
When this "active-low" signal is asserted, the Framer will be asynchronously
reset. Additionally, all outputs will be "tri-stated", and all on-chip registers will
be reset to their default values.
Motorola/Intel Processor Interface Select Mode:
This input pin allows the user to configure the Microprocessor Interface to
interface with either a "Motorola-type" or "Intel-type" microprocessor/micro-
controller. Tying this input pin to VCC, configures the microprocessor interface
to operate in the Motorola mode (e.g., the Framer can be readily interfaced to
a "Motorola type" local microprocessor). Tying this input pin to GND config-
ures the Microprocessor Interface to operate in the Intel Mode (e.g., the
Framer can be readily interfaced to a “Intel type" local microprocessor).
Factory Test Pin:
The user should tie this pin to Ground.
See Description of Pin G4
See Description of Pin G3
See Description of Pin G2
See Description of Pin F3
See Description of Pin A17
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See Description of Pin B8
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Read Data Strobe (Intel Mode):
If the microprocessor interface is operating in the Intel Mode, then this input
will function as the RD (READ STROBE) input signal from the local µP. Once
this active-low signal is asserted, then the Framer will place the contents of
the addressed registers (within the Framer) on the Microprocessor Data Bus
D(7:0). When this signal is negated, the Data Bus will be tri-stated.
Data Strobe (Motorola Mode):
If the microprocessor interface is operating in the Motorola mode, then this pin
will function as the active-low Data Strobe signal.
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See Description of Pin E2
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See Description of Pin G2
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