Renesas rl78 User Manual

RL78/G1A

CHAPTER 10 WATCHDOG TIMER

10.3 Register Controlling Watchdog Timer

The watchdog timer is controlled by the watchdog timer enable register (WDTE).

10.3.1 Watchdog timer enable register (WDTE)

Writing “ACH” to the WDTE register clears the watchdog timer counter and starts counting again.

This register can be set by an 8-bit memory manipulation instruction.

Reset signal generation sets this register to 9AH or 1AH

Note

Figure 10-2. Format of Watchdog Timer Enable Register (WDTE)

Symbol

WDTE

Address: FFFABH After reset: 9AH/1AH

Note

R/W

Note The WDTE register reset value differs depending on the WDTON bit setting value of the option byte

(000C0H). To operate watchdog timer, set the WDTON bit to 1.

WDTON Bit Setting Value

WDTE Register Reset Value

0 (watchdog timer count operation disabled)

1AH

1 (watchdog timer count operation enabled)

9AH

Cautions 1. If a value other than “ACH” is written to the WDTE register, an internal reset signal is

generated.

2. If a 1-bit memory manipulation instruction is executed for the WDTE register, an internal reset

signal is generated.

3. The value read from the WDTE register is 9AH/1AH (this differs from the written value (ACH)).

R01UH0305EJ0200 Rev.2.00

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Jul 04, 2013