Table of Contents
Advertisement
(4) P30 to P37 (Port 3) ∙∙∙ 3-state I/O
Port 3 is an 8-bit I/O port in which input and output can be specified in 1-bit units.
P30 to P37 can function as I/O port pins, input or output pins for the timer/counter, an address bus (A13 to A15)
when memory is expanded externally, and serial interface I/O.
Port/control mode can be selected for each bit.
P31 and P32 can select normal output and N-ch open-drain output.
(a) Port mode
P30 to P37 can be set in 1-bit units as input or output pins according to the contents of the port 3 mode
register (PM3).
(b) Control mode
(i)
TI00, TI01, TI10, TI11, TI4, TI5 (Timer Input 00, 01, 10, 11, 4, 5) ∙∙∙ input
These pins accept external count clock input from timer 0, timer 1, timer 4, and timer 5.
(ii) TO0, TO1, TO4, TO5 (Timer Output 0, 1, 4, 5) ∙∙∙ output
These are the pulse signal output pins of timer 0, timer 1, timer 4, and timer 5.
(iii) A13 to A15 (Address 13 to 15) ∙∙∙ output
These comprise the address bus that is used for external access. These pins operate as the A13 to
A15 bit address output pins within a 22-bit address. The output changes in synchronization with the
rising edge of the clock in the T1 state of the bus cycle. When the timing sets the bus cycle as inactive,
the previous bus cycle's address is retained.
(iv) SI4 (Serial Input 4) ∙∙∙ input
This is the serial receive data input pin of CSI4.
(v) SO4 (Serial Output 4) ∙∙∙ output
This is the serial transmit data output pin for CSI4.
(vi) SCK4 (Serial Clock 4) ∙∙∙ 3-state I/O
This is the I/O pin for CSI4 serial clock.
(5) P40 to P47 (Port 4) ∙∙∙ 3-state I/O
Port 4 is an 8-bit I/O port in which input and output can be specified in 1-bit units.
P40 to P47 can function as I/O port pins and as a time division address/data bus (AD0 to AD7) when memory is
expanded externally.
The I/O signal level uses the bus interface power supply pins BV
(a) Port mode
P40 to P47 can be set in 1-bit units as input or output pins according to the contents of the port 4 mode
register (PM4).
62
CHAPTER 2
PIN FUNCTIONS
DD
User's Manual U13850EJ4V0UM
and BV
as a reference.
SS
Advertisement
Table of Contents
