MITSUBISHI MICROCOMPUTERS
7477/7478 GROUP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Ports P14 – P17
SIOE
SIOM
SRDY
Tr6
Direction register
Data bus
Port latch
Port P1
7
S
RDY
SCS
SIOE
SIOM
SIOE
Tr7
Direction register
Data bus
Port latch
Port P1
6
CLK input
CLK output
SIOE
TE
Tr8
Direction register
Data bus
Port latch
Port P1
5
TXD
SIOE
RE
Tr9
Direction register
Data bus
Data bus
Port latch
Port P1
4
RXD
Pull-up control
register
Tr6 to Tr9 are pull-up transistors.
Fig. 20 Block diagram of ports P14 – P17
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