SH7708 Datasheet, PDF (431/625 Pages) Renesas Technology Corp – SuperH™ RISC engine

Section 15 I/O Ports
15.1 Overview
The has an on-chip 8-bit general-purpose I/O port and an on-chip I/O port for the serial
communication interface (SCI).
15.1.1 Features
The general-purpose I/O port has the following features:
• Direction of each bit of the 8-bit I/O port can be set independently
• When each bit is set for input mode, it is possible to set each bit for independent pull-up
• Ports can be used as I/O ports or as data bus lines, for a maximum data bus width of 32
bits, by setting the PORTEN bit in bus control register 2 (BCR2)
The SCI I/O port has the following features:
• When the I/O port is set to output and the SCI is not enabled, data can be output. This
allows transmission of the break status. SCK pin control is also possible.
• The value of the RxD pin can be read at any time. This enables break detection.
15.1.2 Block Diagram
Figure 15.1 shows a block diagram of the 8-bit general-purpose I/O port.
PORT7 (I/O)/D23 (I/O)
PORT6 (I/O)/D22 (I/O)
PORT5 (I/O)/D21 (I/O)
8-bit
PORT4 (I/O)/D20 (I/O)
port
PORT3 (I/O)/D19 (I/O)
PORT2 (I/O)/D18 (I/O)
PORT1 (I/O)/D17 (I/O)
PORT0 (I/O)/D16 (I/O)
Figure 15.1 8-Bit I/O Port
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