UPD65 NEC [NEC], UPD65 Datasheet - Page 19

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

S
4. TIMER
4.1 Timer Configuration
of a 9-bit down counter (t
1
/LED
REM
The timer is the block used for creating a remote control transmission pattern. As shown in Figure 4-1, it consists
Carrier
synchronous
circuit
8
to t
0
), a flag (t
t
Figure 4-1. Timer Configuration
9
9
) permitting the 1-bit timer output, and a zero detecting circuit.
t
8
Data Sheet U14380EJ2V0DS00
T1
t
7
Bit 2 of control register 0 (P3)
Zero detecting circuit
t
6
9-bit down counter
t
Carrier signal
5
T
t
4
T0
t
3
t
2
t
Timer operation end signal
(HALT # 101B release
1
signal)
t
0
Count
clock
Bit 3 of control register 0 (P3)
PD64A, 65
f
f
X
X
/64
/128
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