HD64F2149 Datasheet, PDF (276/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

Port A Input Data Register (PAPIN)
Bit
7
6
5
4
3
2
1
0
PA7PIN PA6PIN PA5PIN PA4PIN PA3PIN PA2PIN PA1PIN PA0PIN
Initial value
—*
—*
—*
—*
—*
—*
—*
—*
Read/Write
R
R
R
R
R
R
R
R
Note: * Determined by the state of pins PA7 to PA0.
Reading PAPIN always returns the pin states.
8.11.3 Pin Functions
Port A pins also function as keyboard buffer controller I/O pins (PS2AC, PS2AD, PS2BC,
PS2BD, PS2CC, PS2CD), key-sense interrupt input pins (KIN15 to KIN8), expansion A/D
converter input pins (CIN15 to CIN8), and address output pins (A23 to A16). The port A pin
functions are shown in table 8.21.
Table 8.21 Port A Pin Functions
Pin
Selection Method and Pin Functions
PA7/A23/PS2CD/ The pin function is switched as shown below according to the combination of
KIN15/CIN15
operating mode, the KBIOE bit in KBCR2H of the keyboard buffer controller,
the IOSE bit in SYSCR, and bit PA7DDR.
Operating Modes 1, 2 (EXPE = 0), 3
mode
Mode 2 (EXPE = 1)
KBIOE
0
1
0
1
PA7DDR
0
1
—
0
1
—
IOSE
—
—
—
—
0
1
—
Pin function
PA7
input
pin
PA7 PS2CD PA7
output output input
pin
pin
pin
A23 PA7 PS2CD
output output output
pin
pin
pin
KIN15 input pin, CIN15 input pin, PS2CD input pin
When the IICS bit in STCR is set to 1, this pin functions as a bus buffer. This
pin can always be used as the PS2CD, KIN15, or CIN15 input pin.
242