HD6475348R Datasheet, PDF (173/487 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

Pin Functions in Single-Chip Mode: In the single-chip mode (mode 7), each of the port 3 pins
can be designated as an input pin or an output pin, as indicated in figure 9-7, by setting the
corresponding bit in P3DDR to 1 for output or clearing it to 0 for input.
P37 (input/output)
P36 (input/output)
P35 (input/output)
Port
P34 (input/output)
3
P33 (input/output)
P32 (input/output)
P31 (input/output)
P30 (input/output)
Figure 9-7 Port 3 Pin Functions in Single-Chip Mode
9.5 Port 4
9.5.1 Overview
Port 4 is an 8-bit input/output port with the pin configuration shown in figure 9-8. In the
expanded modes it provides the low bits (A7 – A0) of the address bus. In the single-chip mode it
operates as a general-purpose input/output port.
Outputs from port 4 can drive one TTL load and a 90 pF capacitive load. They can also drive a
Darlington transistor pair or LED (with 10 mA current sink).
Pin
Expanded Modes
Single-Chip Mode
P47 / A7
A7 (output)
P47 (input/output)
P46 / A6
A6 (output)
P46 (input/output)
P45 / A5
A5 (output)
P45 (input/output)
Port
P44 / A4
A4 (output)
P44 (input/output)
4
P43 / A3
A3 (output)
P43 (input/output)
P42 / A2
A2 (output)
P42 (input/output)
P41 / A1
A1 (output)
P41 (input/output)
P40 / A0
A0 (output)
P40 (input/output)
Figure 9-8 Pin Functions of Port 4
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