Datasheet

Section 10 I/O Ports
R01UH0309EJ0500 Rev. 5.00 Page 675 of 1408
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
10.16 Port H
Note: Port H is not supported in the H8S/2454 Group.
Port H is a 4-bit I/O port that also has other functions. Port H has the following registers. For the
port function control registers, refer to section 10.18, Port Function Control Registers.
• Port H data direction register (PHDDR)
• Port H data register (PHDR)
• Port H register (PORTH)
• Port function control register 0 (PFCR0)
• Port function control register 2 (PFCR2)
• Port H open drain control register (PHODR)
10.16.1 Port H Data Direction Register (PHDDR)
The individual bits of PHDDR specify input or output for the pins of port H. PHDDR cannot be
read; if it is, an undefined value will be read.
Bit Bit Name Initial Value R/W Description
7 to 4 ⎯ All 0 ⎯ Reserved
3 PH3DDR 0 W
2 PH2DDR 0 W
1 PH1DDR 0 W
0 PH0DDR 0 W
• Modes 1, 2, and 4 Modes 3 and 7 (EXPE = 1)
Pin PH3 functions as the OE output pin when the
OE output enable bit (OEE) and OE output select
bit (OES) are set to 1. Otherwise, pin PH3
functions as the CS7 output pin when bit
PH3DDR is set to 1 while bit CS7E is 1, and as
an input port when the bit is cleared to 0. When
bit CS7E is cleared to 0, pin PH3 is an I/O port,
and its function can be switched with bit
PH3DDR. When areas 2 to 5 are specified as
continuous SDRAM space*, OE output is CKE
output.
Pin PH2 function as the CS6 output pin when bit
PH2DDR is set to 1 while bit CS6E is 1, and as
an I/O port when the bit is cleared to 0. When bit
CS6E is cleared to 0, pin PH2 is an I/O port, and
its function can be switched with bit PH2DDR.