HD64F3437TF16 Datasheet, PDF (740/752 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.

C.10 Port A Block Diagram
PA_n
IICS
Reset
Q
R
D
PA_nDDR
C
WPAD
Reset
R
QD
PA_nODR
C
WPA
RPA
WPAD: Write to PADDR
WPA: Write to port A
RPA: Read port A
n = 0 to 7
Key-sense interrupt
input
KMIMR_n+8
Note: For a block diagram when pins PA₇ to PA₄ are used as bus buffer input/output pins, see section 13,
I²C Bus Interface.
Figure C.10 Port A Block Diagram (Pins PA₀ to PA₇)
711