HD6433044 Datasheet, PDF (285/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

9.10 Port 9
9.10.1 Overview
Port 9 is a 6-bit input/output port that is also used for input and output (TxD₀, TxD₁, RxD₀, RxD₁,
SCK₀, SCK₁) by serial communication interface channels 0 and 1 (SCI0 and SCI1), and for IRQ₅
and IRQ₄ input. See table 9-17 for the selection of pin functions.
The IRQ₅ and IRQ₄ functions are selected by IER settings, regardless of whether the pin is used
for input or output. For details see section 5, Interrupt Controller.
Port 9 has the same set of pin functions in all operating modes. Figure 9-9 shows the pin
configuration of port 9.
Pins in port 9 can drive one TTL load and a 30-pF capacitive load. They can also drive a
darlington transistor pair.
Port 9
Port 9 pins
P9₅ (input/output)/SCK₁ (input/output)/IRQ₅ (input)
P9₄ (input/output)/SCK₀ (input/output)/IRQ₄ (input)
P9₃ (input/output)/RxD₁ (input)
P9₂ (input/output)/RxD₀ (input)
P9₁ (input/output)/TxD₁ (output)
P9₀ (input/output)/TxD₀ (output)
Figure 9-9 Port 9 Pin Configuration
9.10.2 Register Descriptions
Table 9-16 summarizes the registers of port 9.
Table 9-16 Port 9 Registers
Address* Name
H'FFD0
Port 9 data direction register
H'FFD2
Port 9 data register
Note: * Lower 16 bits of the address.
Abbreviation R/W
P9DDR
W
P9DR
R/W
272
Initial Value
H'C0
H'C0