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CHAPTER 9 I/O PORT
9.9.1
Port 6 Registers (PDR6 and DDR6)
This section describes the port 6 registers.
■ Functions of Port 6 Registers
●
Port 6 data register (PDR6)
The PDR6 register indicates the state of each pin of port 6.
●
Port 6 data direction register (DDR6)
The DDR6 register specifies the direction of a data flow (input or output) at each pin (bit) of port 6. When
a DDR6 register bit is "1", the corresponding port (pin) is set as an output port. When the bit is "0", the
port (pin) is set as an input port.
Notes:
• When a resource having output pins is used, the port functions as resource output pins regardless
of the value in the DDR6 register as long as the resource output enable bit corresponding to the
pins is set.
• To use a resource having input pins, reset the DDR6 register bit corresponding to each resource
input pin to "0" to place the port in input mode.Table 9.9-3 lists the functions of the port 6
registers.
Table 9.9-3 Port 6 Register Functions
Register
Data
0
Port 6 data
register (PDR6)
1
Port 6 data
0
direction
register
1
(DDR6)
R/W: Read/write enabled
X
: Undefined
-
: Empty bit
200
During
reading
The output latch is loaded with "0".
The pin is at
When the pin functions as an
the low level.
output port, the pin is set to the low
level.
The output latch is loaded with "1".
The pin is at
When the pin functions as an
the high level.
output port, the pin is set to the
high level.
The direction
The output buffer is turned off to
latch is "0".
place the port in input mode.
The direction
The output buffer is turned on to
latch is "1".
place the port in output mode.
During writing
Read/
Address
Initial value
Write
000006
----XXXX
R/W
H
000016
R/W
H
B
----0000
B
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