Datasheet

Section 8 I/O Ports
Rev. 8.00 Mar. 09, 2010 Page 195 of 658
REJ09B0042-0800
Section 8 I/O Ports
8.1 Overview
The LSI is provided with five 8-bit I/O ports, two 4-bit I/O ports, one 3-bit I/O port, one 8-bit
input-only port, one 1-bit input-only port, and one 6-bit output-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, and A are also used as liquid crystal display segment and common pins, selectable
in 4-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
/IRQ
3
/TMIF External interrupt 3, timer
event input pin TMIF
PMR1
TCRF
P1
6
*
1
None
P1
4
/IRQ
4
/ADTRG External interrupt 4, A/D
converter external trigger
PMR1
AMR
• 4-bit I/O port
• MOS input pull-up
option
P1
3
/TMIG Timer G input capture PMR1
PMR2
Port 3 P3
7
/AEVL
P3
6
/AEVH
Asynchronous counter event
input pins AEVL, AEVH
PMR3
ECCR
P3
5
to P3
3
None PMR2
P3
2
, TMOFH
P3
1
, TMOFL
Timer F output compare
output
PMR3
• 8-bit I/O port
• MOS input pull-up
option
• Large-current
port
*
2
• MOS open drain
output selectable
(only P3
5
)
P3
0
/UD Timer C count up/down
selection input
PMR3