XRT79L71_1 Datasheet, PDF (44/434 Pages) Exar Corporation – 1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC -

XRT79L71
1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC - REGISTER/MAP DESCRIPTION
REV. 1.0.0
BIT NUMBER
NAME
2
General Purpose Data[2]
1
General Purpose Data[1]
TYPE
R/W
R/W
DESCRIPTION
General Purpose Data - GPIO_2:
The exact function of this bit-field depends upon whether Gen-
eral Purpose I/O Pin, GPIO_2 (Pin P8) has been configured to
function as an input or an output pin, as described below.
If GPIO_2 is configured to function as an input pin
If GPIO_2 is configured to function as an input pin, then the user
can monitor the state of this particular input pin by reading out
the state of this bit-field.If this bit-field is set to "0" then it means
that GPIO_2 is currently pulled to a logic "Low" level. Con-
versely, if this bit-field is set to "1", then it means that GPIO_2 is
currently pulled to a logic "High" level.
NOTE: If GPIO_2 is configured to function as an input pin, then
writing to this particular register will have no affect on the
state of this pin.
If GPIO_2 is configured to function as an output pin
If GPIO_2 is configured to function as an output pin, then the
user can control the state of this particular output pin by writing
the appropriate value to this bit-field.
Setting this bit-field to "0" will cause GPIO_2 to be driven to a
logic "Low" level. Conversely, setting this bit-field to "1" will
cause GPIO_2 to be driven to a logic "High" level.
NOTE: GPIO_2 can be configured to function as either an input
or output pin, by writing the appropriate value to Bit 2
(General Purpose Pin Direction[2]) within the Operation
General Purpose Pin Direction Control Register
(Address = 0x014B).
General Purpose Data - GPIO_1:
The exact function of this bit-field depends upon whether Gen-
eral Purpose I/O Pin, GPIO_1 (Pin N8) has been configured to
function as an input or an output pin, as described below.
If GPIO_1 is configured to function as an input pin
If GPIO_1 is configured to function as an input pin, then the user
can monitor the state of this particular input pin by reading out
the state of this bit-field.If this bit-field is set to "0" then it means
that GPIO_1 is currently pulled to a logic "Low" level. Con-
versely, if this bit-field is set to "1", then it means that GPIO_1 is
currently pulled to a logic "High" level.
NOTE: If GPIO_1 is configured to function as an input pin, then
writing to this particular register will have no affect on the
state of this pin.
If GPIO_1 is configured to function as an output pin
If GPIO_1 is configured to function as an output pin, then the
user can control the state of this particular output pin by writing
the appropriate value to this bit-field.Setting this bit-field to "0"
will cause GPIO_1 to be driven to a logic "Low" level. Con-
versely, setting this bit-field to "1" will cause GPIO_1 to be driven
to a logic "High" level.
NOTE: GPIO_1 can be configured to function as either an input
or output pin, by writing the appropriate value to Bit 1
(General Purpose Pin Direction[1]) within the Operation
General Purpose Pin Direction Control Register
(Address = 0x014B).
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