UPD78F0890GK(A)-GAJ-AX NEC, UPD78F0890GK(A)-GAJ-AX Datasheet - Page 271

• 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

10.5 Cautions for Watch Timer
setting bits 0 (WTM0) and 1 (WTM1) of WTM to 1), the interval until the first interrupt request (INTWT) is generated
after the register is set does not exactly match the specification made with bits 2 and 3 (WTM2, WTM3) of WTM.
Subsequently, however, the INTWT signal is generated at the specified intervals.
generated every 0.5 seconds.
Figure 10-4. Example of Generation of Watch Timer Interrupt Request (INTWT) (When Interrupt Period = 0.5 s)
When operation of the watch timer and 5-bit counter is enabled by the watch timer mode control register (WTM) (by
It takes 0.515625 seconds for the first INTWT to be generated (2
WTM0, WTM1
INTWT
CHAPTER 10 WATCH TIMER
0.515625 s
User’s Manual U17554EJ4V0UD
0.5 s
9
× 1/32768 = 0.015625 s longer). INTWT is then
0.5 s
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