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.
Modes 1 to 6 (Expanded Modes):
P6
6
to P6
3
function as bus control output pins (
LWR
,
HWR
,
RD
,
AS
). P6
2
to P6
0
are generic input/output pins, functioning as output port when bits P6
2
DDR
to P6
0
DDR are set to 1 and input port when these bits are cleared to 0.
Mode 7 (Single-Chip Mode):
Port 6 is a generic input/output port. A pin in port 6 becomes an
output port if the corresponding P6DDR bit is set to 1, and an input port if this bit is cleared to 0.
Bit 7 is 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 output data
for pins P6
6
to P6
0
. When a bit in P6DDR is set to 1, if port 6 is read the value of the
corresponding P6DR bit is returned. When a bit in P6DDR is cleared to 0, if port 6 is read the
corresponding pin level is read.
Bit 7 is reserved, cannot be modified, and always read as 1.
P6DR is initialized to H'80 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting.
263
Bit
Initial value
Read/Write
7
—
1
—
6
P6 DDR
0
W
5
P6 DDR
0
W
4
P6 DDR
0
W
3
P6 DDR
0
W
2
P6 DDR
0
W
1
P6 DDR
0
W
0
P6 DDR
0
W
Port 6 data direction 6 to 0
These bits select input or output for port 6 pins
Reserved bit
Bit
Initial value
Read/Write
7
—
1
—
6
P6
0
R/W
6
5
P6
0
R/W
5
4
P6
0
R/W
4
3
P6
0
R/W
3
2
P6
0
R/W
2
1
P6
0
R/W
1
0
P6
0
R/W
0
Reserved bit
Port 6 data 6 to 0
These bits store data for port 6 pins