HD6475348R Datasheet, PDF (167/487 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

Table 9-4 Port 1 Pin Functions in Single-Chip Modes (cont)
Pin
Selection of Pin Functions
P12
P12DDR
0
1
Pin function Input
Output
P11 / E
P11DDR
Pin function
0
Input
1
E clock output
P10 / ø
P10DDR
Pin function
0
Input
1
ø clock output
9.3 Port 2
9.3.1 Overview
Port 2 is a five-bit input/output port with the pin configuration shown in figure 9-2. It functions as
an input/output port only in the single-chip mode. In the expanded modes it is used for output of
bus control signals.
Outputs from port 2 can drive one TTL load and a 90 pF capacitive load. They can also drive a
Darlington transistor pair.
Pin
P24 / WR
Port
P23 / RD
2
P22 / DS
P21 / R/W
P20 / AS
Expanded Modes
WR (output)
RD (output)
DS (output)
R/W (output)
AS (output)
Single-Chip Mode
P24 (input/output)
P23 (input/output)
P22 (input/output)
P21 (input/output)
P20 (input/output)
Figure 9-2 Pin Functions of Port 2
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