UPD78F0537DGA(T)-9EV-A NEC, UPD78F0537DGA(T)-9EV-A Datasheet - Page 294

• Manufacturer Part Number: UPD78F0537DGA(T)-9EV-A
• Description: 8BIT MCU, 128K FLASH, 7KB RAM, SMD
• Manufacturer: NEC

Specifications of UPD78F0537DGA(T)-9EV-A

• Controller Family/series: UPD78
• No. Of I/o's: 55
• Ram Memory Size: 7KB
• Cpu Speed: 20MHz
• No. Of Timers: 8
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 128KB
• Oscillator Type: External, Internal

10.1 Functions of Watch Timer
294
The watch timer has the following functions.
• Watch timer
• Interval timer
The watch timer and the interval timer can be used simultaneously.
Figure 10-1 shows the watch timer block diagram.
Remark
f
PRS
f
SUB
/2
7
f
f
f
f
PRS
SUB
W
WX
:
: f
: Peripheral hardware clock frequency
: Subsystem clock frequency
f
W
Watch timer clock frequency (f
W
or f
f
W
/2
W
4
/2
f
W
9
/2
11-bit prescaler
5
f
W
Figure 10-1. Block Diagram of Watch Timer
/2
6
f
WTM7
W
/2
CHAPTER 10 WATCH TIMER
7
Clear
f
W
/2
User’s Manual U17260EJ6V0UD
8
WTM6
f
W
/2
10
PRS
f
W
Internal bus
/2
/2
11
7
f
WTM5
W
or f
/2
9
SUB
)
WTM4
f
WX
5-bit counter
WTM3
Watch timer operation
mode register (WTM)
Clear
WTM2
f
f
WX
WX
WTM1
/2
/2
4
5
WTM0
INTWT
INTWTI