UPD62A NEC, UPD62A Datasheet - Page 17

• Manufacturer Part Number: UPD62A
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER FOR INFRARED REMOTE CONTROL TRANSMISSION
• Manufacturer: NEC

3.3 Control Register 0 (P3)
Control register 0 consists of 8 bits. The contents that can be controlled are as shown below.
When reset, this register becomes 0000 0011B.
b
b
b
b
Remark
0
2
3
4
:
:
and b
and b
5
1
: These bits specify the carrier frequency and duty ratio of the REM output.
: These bits specify the high-order 2 bits (DP
This bit specifies the availability of the carrier of the frequency specified by b
“0” = ON (with carrier); “1” = OFF (without carrier; high level)
This bit changes the carrier frequency and the timer clock’s frequency division ratio.
“0” = 1/1 (carrier frequency: the specified value of b
“1” = 1/2 (carrier frequency: half of the specified value of b
: don’t care
Bit
Name
Set
value
After reset
0
0
b
3
0
1
0
1
0
1
b
Table 3-5. Timer Clock and Carrier Frequency Settings
2
b
Fixed
to 0
0
7
—
0
0
1
1
0
0
1
1
b
1
Table 3-4. Control Register 0 (P3)
b
Fixed
to 0
0
6
—
0
1
0
1
0
1
0
1
b
Data Sheet U14474EJ1V0DS00
0
b
DP (Data pointer) TCTL
DP
0
1
0
5
9
f
f
X
X
/64
/128
Timer Clock
b
DP
0
1
0
4
8
8
and DP
b
1/1
1/2
0
3
0
and b
9
) of the ROM data pointer.
Carrier Frequency (Duty Ratio)
f
f
f
f
Without carrier (high level)
f
f
f
f
Without carrier (high level)
X
X
X
X
X
X
X
X
/8 (Duty 1/2)
/64 (Duty 1/2)
/96 (Duty 1/2)
/96 (Duty 1/3)
/16 (Duty 1/2)
/128 (Duty 1/2)
/192 (Duty 1/2)
/192 (Duty 1/3)
0
1
b
CARY
ON
OFF
0
; timer clock: f
2
and b
1
Refer to Table 3-5.
; timer clock: f
b
1
MOD
1
1
X
/64)
b
MOD
1
0
0
and b
0
X
/128)
1
.
PD62A
17