(1) Ports P0—P2
Pull-up control
Direction register
Data bus
Port latch
*1
(3) Ports P32,P33,P35—P37
Direction register
Data bus
Port latch
*1
MITSUBISHI MICROCOMPUTERS
3807 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
(2) Ports P30,P31
Real time port output selection bit
Direction register
Data bus
Port latch
Data for real time port
(4) Port P34
Clock output control
Direction register
Data bus
Port latch
Clock output
(5) Port P40
Port XC switch bit
Direction register
Data bus
Port latch
(6) Port P41
Port XC switch bit
Direction register
Data bus
Port latch
Oscillator
Port P41
Port XC switch bit
Sub-clock oscillating circuit input
(7) Ports P42,P43,P52,P53
Direction register
Data bus
Port latch
(8) Port P44
Serial I/O1 enable bit
Receive enable bit
Direction register
Data bus
Port latch
Interrupt input
Timer X input (P42)
Timer Y input (P43)
RTP trigger input (P53)
except P52
serial I/O1 input
*1 Either CMOS input level or TTL input level can be selected as an input level for ports P20 to P27 and P32 by P2•P32 input level selection bit.
Fig. 10. Port block diagram (1)
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