HD6473258CP10 Datasheet, PDF (87/301 Pages) Renesas Technology Corp – Hitachi Single-Chip Microcomputer

Table 5-1. Auxiliary Functions of Input/Output Ports
I/O Port
Port 1
Port 2
Port 3
Port 4
Port 5
Port 6
Port 7
Auxiliary functions
Address bus (low)
Address bus (high)
Data bus or parallel handshaking data lines
System clock and E clock output, 8-bit timer input and output
Serial communication interface
Free-running timer input and output, IRQ2 to IRQ0
Bus control and parallel handshaking control
(Note 1)
(Note 1)
(Note 2)
Notes:
*1 Selected automatically in mode 1; software-selectable in mode 2
*2 Data bus function is selected automatically in modes 1 and 2
5.2 Port 1
Port 1 is an 8-bit input/output port that also provides the low bits of the address bus. The function
of port 1 depends on the MCU mode as indicated in table 5-2.
Table 5-2. Functions of Port 1
Mode 1
Address bus (low)
(A7 to A0)
Mode 2
Input port or
Address bus (low)
(A7 to A0)*
Mode 3
Input/output port
* Depending on the bit settings in the data direction register: 0—input pin; 1—address pin
Pins of port 1 can drive a single TTL load and a 90-pF capacitive load when they are used as output
pins. They can also drive light-emitting diodes or a Darlington pair.
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