Datasheet

Section 8 I/O Ports
Rev. 2.00 Sep. 28, 2009 Page 250 of 870
REJ09B0429-0200
8.15.3 Port F Input Data Register (PFPIN)
PFPIN indicates the pin states of port F.
Bit Bit Name Initial Value R/W Description
7 to 4 ⎯ ⎯ ⎯ Reserved
Undefined value is read from this bit.
3
2
1
0
PF3PIN
PF2PIN
PF1PIN
PF0PIN
Undefined*
Undefined*
Undefined*
Undefined*
R
R
R
R
When this register is read, the pin states are read.
Since this register is allocated to the same address as
PFDDR, writing to this register writes data to PFDDR
and the port F setting is changed.
Note: The initial value of these pins is determined in accordance with the state of pins PF3 to
PF0.
8.15.4 Pin Functions
Port F is a 4-bit I/O port. The relationship between the register settings and the pin function is
shown below.
• PF3/RS11, PF2/RS10, PF1/RS9, PF0/RS8
The pin function is switched as shown below according to the PFnDDR bit.
PFnDDR 0 1
Pin function PFn input pin PFn output pin
[Legend] n = 3 to 0