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CHAPTER 6 PORT FUNCTIONS
P-ch
WR
PM
WR
PORT
RD
WR
PUO
V
DD
Selector
PUO5
Output Latch
(P50 to P57)
PM50-PM57
Internal bus
P50/A8
P57/A15
6.2.7 Port 5
Port 5 is an 8-bit input/output port with output latch. P50 to P57 pins can specify the input mode/output mode in
1-bit units with the port mode register 5 (PM5). When P50 to P57 pins are used as input ports, an on-chip pull-up
resistor can be used to them in 8-bit units with a pull-up resistor option register L (PUOL).
Port 5 can drive LEDs directly.
Alternate function includes address bus function in external memory expansion mode.
RESET input sets port 5 to input mode.
Figure 6-12 shows a block diagram of port 5.
Figure 6-12. P50 to P57 Block Diagram
PUO : Pull-up resistor option register
PM
: Port mode register
RD
: Port 5 read signal
WR : Port 5 write signal
Содержание PD78052
Страница 2: ...2 MEMO ...
Страница 8: ...8 MEMO ...
Страница 16: ...16 MEMO ...
Страница 36: ...36 MEMO ...
Страница 158: ...158 MEMO ...
Страница 174: ...174 MEMO ...
Страница 240: ...240 MEMO ...
Страница 260: ...260 MEMO ...
Страница 340: ...340 MEMO ...
Страница 392: ...392 MEMO ...
Страница 438: ...438 MEMO ...
Страница 482: ...482 CHAPTER 20 REAL TIME OUTPUT PORT MEMO ...
Страница 510: ...510 MEMO ...
Страница 524: ...524 MEMO ...
Страница 560: ...560 MEMO ...
Страница 576: ...576 MEMO ...
Страница 598: ...598 MEMO ...
Страница 602: ...602 MEMO ...