HD6473032F Datasheet, PDF (161/572 Pages) Hitachi Semiconductor – Hitachi Microcomputer

7.8 Port 8
7.8.1 Overview
Port 8 is a 4-bit input/output port that is also used for IRQ₃ to IRQ₀ input. Figure 7-17 shows the
pin configuration of port 8.
Pin P8₀ functions as input/output pin or as an IRQ₀ input pin. Pins P8₃ to P8₁ function as either
input pins or IRQ₃ to IRQ₁ input pins in mode 1, and as input/output pins or IRQ₃ to IRQ₁ input
pins in modes 2 and 3.
Pins in port 8 can drive one TTL load and a 90-pF capacitive load. They can also drive a darlington
transistor pair. Pins P8₂ to P8₀ have Schmitt-trigger inputs.
Port 8
Port 8 pins Mode 1
Modes 2 and 3
P8₃/IRQ₃
P8₂/IRQ₂
P8₁/IRQ₁
P8₀/IRQ₀
P8₃ (input)/IRQ₃ (input)
P8₃ (input/output)/IRQ₃ (input)
P8₂ (input)/IRQ₂ (input)
P8₂ (input/output)/IRQ₂ (input)
P8₁ (input)/IRQ₁ (input)
P8₁ (input/output)/IRQ₁ (input)
P8₀ (input/output)/IRQ₀ (input) P8₀ (input/output)/IRQ₀ (input)
Figure 7-17 Port 8 Pin Configuration
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