UPD78F0138 NEC, UPD78F0138 Datasheet - Page 232

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

9.2 Configuration of Watch Timer
9.3 Register Controlling Watch Timer
232
The watch timer includes the following hardware.
The watch timer is controlled by the watch timer operation mode register (WTM).
• Watch timer operation mode register (WTM)
This register sets the watch timer count clock, enables/disables operation, prescaler interval time, and 5-bit
counter operation control.
WTM is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input clears WTM to 00H.
Counter
Prescaler
Control register
Item
Table 9-3. Watch Timer Configuration
5 bits × 1
11 bits × 1
Watch timer operation mode register (WTM)
CHAPTER 9 WATCH TIMER
User’s Manual U16228EJ2V0UD
Configuration