h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 241

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 9 I/O Ports
Section 9 I/O Ports
9.1
Overview
The H8S/2646 Group has 13 I/O ports (ports 1 to 3, 5, A to F, H, J, and K), and two input-only
port (ports 4 and 9).
Table 9.1 summarizes the port functions. The pins of each port also have other functions.
Each I/O port includes a data direction register (DDR) that controls input/output, a data register
(DR) that stores output data, and a port register (PORT) used to read the pin states. The input-only
ports do not have a DR or DDR register.
Ports A to E have a built-in pull-up MOS function, and in addition to DR and DDR, have a MOS
input pull-up control register (PCR) to control the on/off state of MOS input pull-up.
Ports 3, and A to F include an open-drain control register (ODR) that controls the on/off state of
the output buffer PMOS.
When ports A to F are used as the output pins for expanded bus control signals, they can drive one
TTL load plus a 50pF capacitance load. Ports other than A to F can drive one TTL load and a
30pF capacitance load. All I/O ports can drive Darlington transistors when set to output. Ports 1
and A to C can drive a LED (10 mA sink current), and some of the pins in ports A to E and F can
be used as LCD driver pins.
See appendix C, I/O Port Block Diagrams, for a block diagram of each port.
Rev. 5.00 Sep 22, 2005 page 215 of 1136
REJ09B0257-0500