HD6413007F20 Datasheet, PDF (278/798 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

8. I/O Ports
8.2 Port 4
8.2.1 Overview
Port 4 is an 8-bit input/output port with the pin configuration shown in figure 8.1.
When the bus width control register (ABWCR) designates areas 0 to 7 all as 8-bit-access areas, the
chip operates in 8-bit bus mode and port 4 is a generic input/output port. When at least one of
areas 0 to 7 is designated as a 16-bit-access area, the chip operates in 16-bit bus mode and port 4
becomes part of the data bus.
Port 4 has software-programmable built-in pull-up transistors.
Pins in port 4 can drive one TTL load and a 90-pF capacitive load. They can also drive a
darlington transistor pair.
Port 4 pins
Modes 1 to 4
Port 4
P4₇ /D₇
P4₆ /D₆
P4₅ /D₅
P4₄ /D₄
P4₃ /D₃
P4₂ /D₂
P4₁ /D₁
P4₀ /D₀
P4₇ (input/output)/D₇ (input/output)
P4₆ (input/output)/D₆ (input/output)
P4₅ (input/output)/D₅ (input/output)
P4₄ (input/output)/D₄ (input/output)
P4₃ (input/output)/D₃ (input/output)
P4₂ (input/output)/D₂ (input/output)
P4₁ (input/output)/D₁ (input/output)
P4₀ (input/output)/D₀ (input/output)
Figure 8.1 Port 4 Pin Configuration
Rev.5.00 Sep. 12, 2007 Page 248 of 764
REJ09B0396-0500