141
CHAPTER 6 PORT FUNCTIONS
Figure 6-13. P60 to P63 Block Diagram
PM : Port mode register
RD : Port 6 read signal
WR : Port 6 write signal
Figure 6-14. P64 to P67 Block Diagram
PUO : Pull-up resistor option register
PM : Port mode register
RD : Port 6 read signal
WR : Port 6 write signal
WRPM
WRPORT
RD
AVDD
Selector
Output Latch
(P60 to P63)
PM60 to PM63
Internal bus
P60 to P63
Mask Option Resistor
Mask ROM products
only. PROM versions
have no pull-up resistor.
P-ch
WR
PM
WR
PORT
RD
WR
PUO
AV
DD
Selector
PUO6
Output Latch
(P64 to P67)
PM64 to PM67
Internal bus
P64/RD,
P65/WR,
P66/WAIT,
P67/ASTB