Datasheet

Section 8 I/O Ports
Rev. 6.00 Aug 04, 2006 page 203 of 680
REJ09B0145-0600
Section 8 I/O Ports
8.1 Overview
The H8/3847R Group, H8/3847S Group and H8/38347 Group are provided with eight 8-bit I/O
ports, one 4-bit I/O port, one 3-bit I/O port, one 8-bit input-only port, one 4-bit input-only port,
and one 1-bit input-only port. Table 8.1 indicates the functions of each port.
Each port has of a port control register (PCR) that controls input and output, and a port data
register (PDR) for storing output data. Input or output can be assigned to individual bits.
See section 2.9.2, Notes on Bit Manipulation, for information on executing bit-manipulation
instructions to write data in PCR or PDR.
Ports 5, 6, 7, 8, 9, and A are also used as liquid crystal display segment and common pins,
selectable in 8-bit units.
Block diagrams of each port are given in Appendix C, I/O Port Block Diagrams
Table 8.1 Port Functions
Port Description Pins Other Functions
Function
Switching
Registers
Port 1 P1
7
to P1
5
/IRQ
3
to
IRQ
1
/TMIF, TMIC
External interrupts 3 to 1
Timer event interrupts
TMIF, TMIC
PMR1,
TCRF,
TMC
P1
4
/IRQ
4
/ADTRG External interrupt 4 and A/D
converter external trigger
PMR1,
AMR
P1
3
/TMIG Timer G input capture input PMR1
P1
2
, P1
1
/
TMOFH, TMOFL
Timer F output compare output PMR1
• 8-bit I/O port
• MOS input pull-up
option
P1
0
/TMOW Timer A clock output PMR1
Port 2 P2
0
/SCK
1
P2
1
/SI
1
P2
2
/SO
1
SCI1 data output (SO
1
), data input
(SI
1
), clock input/output (SCK
1
)
PMR2
• 8-bit I/O port
• Open-drain output
option
• Large-current port
(H8/3847R Group,
H8/38347 Group
and H8/38447
Group)
P2
7
to P2
3
None