HD64F3437TF16 Datasheet, PDF (148/752 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.

7.4.3 Pin Functions in Each Mode
Port 3 has different pin functions in different modes. A separate description for each mode is given
below.
Pin Functions in Modes 1 and 2: In mode 1 (expanded mode with on-chip ROM disabled) and
mode 2 (expanded mode with on-chip ROM enabled), port 3 is automatically used for the
input/output pins of the data bus (D₇ to D₀). Figure 7.10 shows the pin functions in modes 1 and 2.
Port 3
Modes 1 and 2
D₇ (input/output)
D₆ (input/output)
D₅ (input/output)
D₄ (input/output)
D₃ (input/output)
D₂ (input/output)
D₁ (input/output)
D₀ (input/output)
Figure 7.10 Pin Functions in Modes 1 and 2 (Port 3)
119