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(4) P30 to P37 (Port 3) ··· 3-state I/O
Port 3 is an 8-bit I/O port in which input and output pins can be specified bitwise.
P30 to P37 can function as I/O port pins and can also operate as input or output pins for the timer/counter.
These pins can be set bitwise to port mode or a control mode.
(a) Port mode
P30 to P37 can be set bitwise as input or output pins according to the contents of port 3 mode register
(PM3).
(b) Control modes
P30 to P37 can be set bitwise to port mode or a control mode according to the contents of the port 3 register
(P3) and port 3 mode register (PM3).
(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 pins output pulse signals from timer 0, timer 1, timer 4, and timer 5.
(iii) A13 to A15 (Address 13 to 15) ··· output
These are address bus that is used for external access. These pins operate as 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.
(5) P40 to P47 (Port 4) ··· 3-state I/O
Port 4 is an 8-bit I/O port in which input and output pins can be specified bitwise.
P40 to P47 can function as I/O port pins and can also operate as a time division address/data bus (AD0 to AD7)
when using external memory expansion. These pins can be set bitwise to port mode or a control mode.
The I/O signal level uses the bus interface power supply pins BV
(a) Port mode
P40 to P47 can be set bitwise as input or output pins according to the contents of port 4 mode register
(PM4).
CHAPTER 2
PIN FUNCTIONS
DD
and BV
as a reference.
SS
41
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