HD64F3437TF16 Datasheet, PDF (173/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

7.10.3 Pin Functions
Port 9 has one set of pin functions in modes 1 and 2, and a different set of pin functions in mode 3.
The pins are multiplexed with IRQ₀ to IRQ₂ input, bus control signal input/output, A/D converter
input, system clock (ø) output, host interface input (ECS₂, EIOW), and I²C data input/output
(SDA). Table 7.19 indicates the pin functions of port 9.
Table 7.19 Port 9 Pin Functions
P9₇/WAIT/SDA
Bit ICE in ICCR, bit P9₇DDR, the wait mode as determined by WSCR, and the
operating mode select the pin function as follows
Operating mode
Modes 1 and 2
Mode 3
Wait mode
WAIT
WAIT
—
used
not used
ICE
—
0
1
0
1
P9₇DDR
Pin function
—
WAIT
input
0
P9₇
input
1
P9₇
output
—
SDA
input/
output
0
P9₇
input
1
—
P9₇ SDA
output input/
output
P9₆/ø
P9₅/AS
P9₄/WR
Bit P9₆DDR and the operating mode select the pin function as follows
Operating mode Modes 1 and 2
Mode 3
P9₆DDR
Pin function
Always 1
ø output
0
P9₆ input
1
ø output
Bit P9₅DDR and the operating mode select the pin function as follows
Operating mode Modes 1 and 2
Mode 3
P9₅DDR
Pin function
—
AS output
0
P9₅ input
1
P9₅ output
Bit P9₄DDR and the operating mode select the pin function as follows
Operating mode Modes 1 and 2
Mode 3
P9₄DDR
Pin function
—
WR output
0
P9₄ input
1
P9₄ output
144