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CHAPTER 4 PORT FUNCTIONS
User’s Manual U19780EJ2V0UD
101
Figure 4-15. Block Diagram of P42
WR
PU
RD
WR
PORT
WR
PM
PU42
PM42
V
DD
P-ch
PM4
PU4
P4
P42/PCL/SSI10/INTP9
Internal bus
Selector
Alternate
function
Alternate
function
Output latch
(P42)
P4:
Port register 4
PU4:
Pull-up resistor option register 4
PM4:
Port mode register 4
RD: Read
signal
WR
××
: Write
signal