UPD78F0890GK(A)-GAJ-AX NEC, UPD78F0890GK(A)-GAJ-AX Datasheet - Page 266

• Manufacturer Part Number: UPD78F0890GK(A)-GAJ-AX
• Description: 8BIT MCU, 128K FLASH, 7K RAM, LQFP
• Manufacturer: NEC

Specifications of UPD78F0890GK(A)-GAJ-AX

• Controller Family/series: UPD78F
• No. Of I/o's: 55
• Ram Memory Size: 7KB
• Cpu Speed: 20MHz
• No. Of Timers: 10
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 128KB
• Oscillator Type: External, Internal

Remark
Remark
10.2 Configuration of Watch Timer
266
2
2
2
2
2
2
2
2
2
2
2
2
4
5
13
14
4
5
6
7
8
9
10
11
/f
/f
/f
/f
/f
/f
/f
/f
Interrupt Time
Interrupt Time
(1) Watch timer
(2) Interval timer
The watch timer includes the following hardware.
/f
/f
/f
/f
W
W
W
W
W
W
W
W
W
W
W
W
When the high-speed system clock or subsystem clock is used, interrupt requests (INTWT) are generated at
preset intervals.
Interrupt requests (INTWTI) are generated at preset time intervals.
f
f
f
f
f
f
PRS
SUB
W
PRS
SUB
W
:
:
: Peripheral hardware clock frequency
: Subsystem clock frequency
: Peripheral hardware clock frequency
: Subsystem clock frequency
Watch timer clock frequency (f
Watch timer clock frequency (f
488
977
0.25 s
0.5 s
488
977
1.95 ms
3.91 ms
7.81 ms
15.6 ms
31.3 ms
62.5 ms
When Operated at
When Operated at
f
f
SUB
SUB
Counter
Prescaler
Control register
μ
μ
μ
μ
= 32.768 kHz
s
s
= 32.768 kHz
s
s
Item
Table 10-1. Watch Timer Interrupt Time
Table 10-2. Interval Timer Interval Time
Table 10-3. Watch Timer Configuration
0.51 ms
1.03 ms
0.26 s
0.53 s
0.51 ms
1.03 ms
2.05 ms
4.1 ms
8.2 ms
16.4 ms
32.75 ms
65.55 ms
When Operated at
When Operated at
5 bits × 1
11 bits × 1
Watch timer operation mode register (WTM)
f
f
PRS
PRS
CHAPTER 10 WATCH TIMER
User’s Manual U17554EJ4V0UD
= 4 MHz
= 4 MHz
PRS
PRS
/2
/2
7
7
or f
or f
SUB
SUB
0.210 s
0.419 s
410
819
)
410
820
1.64 ms
3.28 ms
6.55 ms
13.1 ms
26.2 ms
52.4 ms
)
When Operated at
When Operated at
Configuration
f
f
PRS
μ
μ
PRS
μ
μ
s
s
s
s
= 5 MHz
= 5 MHz
205
410
0.105 s
0.210 s
205
410
820
1.64 ms
3.28 ms
6.55 ms
13.1 ms
26.2 ms
When Operated at
When Operated at
f
f
PRS
PRS
μ
μ
μ
μ
μ
s
s
s
s
s
= 10 MHz
= 10 MHz
102
205
520
0.105 s
102
205
410
820
1.64 ms
3.28 ms
6.55 ms
13.1 ms
When Operated at
When Operated at
f
f
PRS
PRS
μ
μ
μ
μ
μ
μ
μ
s
s
s
s
s
s
s
= 20 MHz
= 20 MHz