UPD65 NEC [NEC], UPD65 Datasheet - Page 14

• Manufacturer Part Number: UPD65
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER FOR INFRARED REMOTE CONTROL TRANSMISSION
• Manufacturer: NEC [NEC]

3. PORT REGISTERS (PX)
14
The K
At reset, port register values are shown below.
Note
I/O
K
port, the K
K
: Refers to the value based on the K
0
0
I/O7
I3
DP
Note When in OFF mode, “1” is normally read.
K
K
I
0
I/O6
K
K
S
S
S
I2
port, the special ports (S
Port Name
10
I/O
I
0
1
2
/LED
Table 3-1. Relationship between Ports and their Read/Write
P
P
P
P
10
11
13
14
pull-down
K
DP
K
K
I/O5
I1
I
9
Figure 3-1. Port Register Organization
Pin state
Pin state
Pin state
Pin state
Pin state
P3 (Control register 0)
P4 (Control register 1)
pull-down
S
Read
K
DP
K
0
Port Register
I/O4
/S
I0
8
1
INPUT Mode
Data Sheet U14380EJ2V0DS00
P0
P1
0
STOP release
, S
S
TCTL
I
K
1
1
/LED
S
pin state.
Output latch
/LED, S
I/O3
2
Write
—
—
—
—
S
1
/LED mode
CARY
2
), and the control register are treated as port registers.
K
S
I/O2
0
P
P
P
P
Output latch
Note
Pin state
00
01
03
04
K
I/O
MOD
Read
K
—
—
S
mode S
I/O1
OUTPUT Mode
2
1
MOD
0
K
mode
Output latch
I/O0
1
0
Write
—
—
—
—
FFH
03H
26H
FH
Note
At Reset
PD64A, 65