HD643303x Hitachi, HD643303x Datasheet - Page 155

• Manufacturer Part Number: HD643303x
• Description: Hitachi Microcomputer
• Manufacturer: Hitachi

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.
Mode 1: Pins P6
input/output pin. When P6
input pin. The P6
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
P6
5
Bit
Initial value
Read/Write
Bit
Initial value
Read/Write
to P6
3
and P6
5
5
0
DDR to P6
to P6
.
Reserved bit
—
—
—
—
7
1
Reserved bit
7
1
3
function as bus control output pins (WR, RD, AS). P6
0
DDR is set to 1, P6
3
DDR bit settings are ignored.
R/W
—
—
6
0
W
6
0
P6 DDR
R/W
P6
5
5
0
W
5
0
5
0
140
is an output pin, and when P6
P6 DDR
R/W
P6
4
4
0
W
4
0
Port 6 data direction 6 to 0
These bits select input or output for port 6 pins
4
P6 DDR
R/W
P6
Port 6 data 5 to 3, 0
These bits store data for port 6 pins
3
W
3
0
3
0
3
R/W
—
—
W
2
0
2
0
0
DDR is 0, P6
0
R/W
functions as an
—
—
W
1
0
1
0
P6 DDR
R/W
P6
0
W
0
0
0
0
0
0
is an