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8.1.7
Port 7
Port 7 is an 8-bit input port. Port 7 pins can also function as the A/D converter analog input pins.
Port 7 has the following register.
• Port 7 input data register (P7PIN)
(1)
Port 7 Input Data Register (P7PIN)
P7PIN indicates the states of the port 7 pins.
Bit
Bit Name
7
P77PIN
6
P76PIN
5
P75PIN
4
P74PIN
3
P73PIN
2
P72PIN
1
P71PIN
0
P70PIN
Note:
* The initial values are determined in accordance with the pin states of P77 to P70.
(2)
Pin Functions
Each pin of port 7 can also be used as the analog input pins of the A/D converter (AN0 to AN7).
• P77/AN7
The pin function is switched as shown below according to the CH2 to CH0 bits in ADCSR of
the A/D converter. Do not set these bits to other values than those shown in the following
table.
CH2 to CH0
Pin function
Initial Value
R/W
Undefined*
R
Undefined*
R
Undefined*
R
Undefined*
R
Undefined*
R
Undefined*
R
Undefined*
R
Undefined*
R
B'111
AN7 input pin
Description
When this register is read, the pin states are read.
Since this register is allocated to the same address as
PBDDR, writing to this register writes data to PBDDR
and the port B setting is changed.
Rev. 1.00 Mar. 12, 2008 Page 225 of 1178
Section 8 I/O Ports
Other than B'111
P77 input pin
REJ09B0403-0100
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