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CHAPTER 6 PORT FUNCTIONS
P-ch
WR
PM
WR
PORT
RD
WR
PUO
V
DD
Selector
PUO2
Output Latch
(P22, P27)
PM22, PM27
Internal bus
Dual Function
P22/SCK1,
P27/SCK0/SCL
Figure 6-8. Block Diagram of P22 and P27
PUO : Pull-up resistor option register
PM : Port mode register
RD : Port 2 read signal
WR : Port 2 write signal
