CHAPTER 2 PIN FUNCTIONS
User’s Manual U13850EJ6V0UD
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(4) P30 to P37 (Port 3) ··· 3-state I/O
P30 to P37 constitute an 8-bit I/O port that can be set to input or output in 1-bit units.
P30 to P37 can also function as input or output pins for the timer/counter, an address bus (A13 to A15) when
memory is expanded externally, and serial interface I/O.
P33 and P34 can be selected as normal output or N-ch open-drain output.
(a) Port function
P30 to P37 can be set to input or output in 1-bit units using the port 3 mode register (PM3).
(b) Alternate functions
(i)
TI00, TI01, TI10, TI11, TI4, TI5 (Timer input 00, 01, 10, 11, 4, 5) ··· input
These are the external count clock input pins of 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 bus 13 to 15) ··· output
These comprise an 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 to 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 of CSI4.
(vi) SCK4 (Serial clock 4) ··· 3-state I/O
This is the I/O pin of the CSI4 serial clock.
Содержание V850/SB1
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