Electronics America 8-Bit Single-Chip Microcontrollers User's Manual

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