HD6473032F Datasheet, PDF (155/572 Pages) Hitachi Semiconductor – Hitachi Microcomputer

Port 6 Data Direction Register (P6DDR): P6DDR is an 8-bit write-only register that can select
input or output for each pin in port 6.
Bit
7
—
Initial value
1
Read/Write
—
6
5
4
3
2
— P6₅DDR P6₄DDR P6₃DDR —
0
0
0
0
0
W
W
W
W
W
1
0
— P6₀DDR
0
0
W
W
Reserved bit
Port 6 data direction 6 to 0
These bits select input or output for port 6 pins
Mode 1: Pins P6₅ to P6₃ function as bus control output pins (WR, RD, AS). P6₀ functions as an
input/output pin. When P6₀DDR is set to 1, P6₀ is an output pin, and when P6₀DDR is 0, P6₀ is an
input pin. The P6₅DDR to P6₃DDR bit settings are ignored.
Modes 2 and 3: Port 6 is a generic input/output port. A pin in port 6 becomes an output pin if the
corresponding P6DDR bit is set to 1, and an input pin if this bit is cleared to 0. Bits 7, 6, 2, and 1
are reserved.
P6DDR is a write-only register. Its value cannot be read. All bits return 1 when read.
P6DDR is initialized to H'80 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting. If a P6DDR bit is set to 1, the corresponding pin maintains its output
state in software standby mode.
Port 6 Data Register (P6DR): P6DR is an 8-bit readable/writable register that stores data for pins
P6₅ to P6₃ and P6₀.
Bit
7
6
5
4
3
2
1
0
—
Initial value
1
—
P6 ₅
P6 ₄
P6 ₃
—
0
0
0
0
0
—
P6 ₀
0
0
Read/Write
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reserved bit
Port 6 data 5 to 3, 0
These bits store data for port 6 pins
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