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CHAPTER 6 PORT FUNCTIONS
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 connected to them in 8-bit units with a pull-up resistor option register L (PUOL).
Port 5 can drive LEDs directly.
Dual-functions include 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. Block Diagram of P50 to P57
PUO : Pull-up resistor option register
PM
: Port mode register
RD
: Port 5 read signal
WR : Port 5 write signal
P-ch
WR
PM
WR
PORT
RD
WR
PUO
V
DD
Selector
PUO5
Output Latch
(P50 to P57)
PM50 to PM57
Internal bus
P50/A8 to
P57/A15
Содержание PD78076
Страница 2: ...2 MEMO ...
Страница 12: ...12 MEMO ...
Страница 48: ...48 MEMO ...
Страница 64: ...64 MEMO ...
Страница 82: ...82 MEMO ...
Страница 100: ...100 MEMO ...
Страница 130: ...130 MEMO ...
Страница 180: ...180 MEMO ...
Страница 222: ...222 MEMO ...
Страница 248: ...248 MEMO ...
Страница 288: ...288 MEMO ...
Страница 308: ...308 MEMO ...
Страница 364: ...364 MEMO ...
Страница 494: ...494 MEMO ...
Страница 526: ...526 MEMO ...
Страница 544: ...544 MEMO ...
Страница 558: ...558 MEMO ...
Страница 580: ...580 MEMO ...
Страница 596: ...596 MEMO ...
Страница 598: ...598 MEMO ...
Страница 626: ...626 MEMO ...