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Register, 1 rsrr: watchdog timer control register, Register 4.1 rsrr: watchdog timer control register – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 20 Software Watchdog Timer

4.Register

4. Register

4.1 RSRR: Watchdog Timer Control Register

This register is used to set watchdog timer periods, and execute the startup control.

(This register also functions as the reset cause register that stores previously generated reset causes.)

Note: Refer also to “

Chapter 9 Reset (Page No.139)

”.

• RSRR: Address 0480h (Access: Byte, Half-word)

(For the attributes, refer to “

Meaning of Bit Attribute Symbols (Page No.10)

”.)

The watchdog timer starts once it writes the watchdog timer control register.

• Bit7: Initialization reset occurred flag

Indicates whether a reset (INIT) was triggered by INIT pin input.

The initialization reset occurred flag (INIT) is cleared to “0” after reading.

• Bit6: Hardware Standby reset occurred flag

Indicates whether a reset (INIT) was triggered by HST pin input.

The hardware standby reset occurred flag (HSTB) is cleared to “0” after reading.

• Bit5: Watchdog reset occurred flag

Indicates whether a reset (INIT) was triggered by the watchdog timer.

The watchdog reset occurred flag (WDOG) is cleared to “0” after reading.

• Bit4: External reset occurred flag

Indicates whether a reset (RST) was triggered by the RST pin input.

The external reset occurred flag (ERST) is cleared to “0” after reading.

• Bit3: Software reset occurred flag

Indicates whether a software reset has been triggered by writing to the software reset bit (STCR.SRST).

7

6

5

4

3

2

1

0

bit

INIT

HSTB

WDOG

ERST

SRST

LINIT

WT1

WT0

1

0

0

0

0

0

0

0

Initial value

(INIT pin input)

-

-

-

X

X

-

0

0

Initial value (Watchdog reset)

X

X

X

-

-

X

0

0

Initial value (Software reset)

R/WX

R/WX

R/WX

R/WX

R/WX

R/WX

R/W

R/W

Attribute

INIT

Meaning

0

No INIT has been triggered by the INIT pin input.

1

INIT has been triggered by the INIT pin input.

HSTB

Meaning

0

No INIT has been triggered by the HST pin input.

1

INIT has been triggered by the HST pin input.

WDOG

Meaning

0

No INIT has been triggered by the watchdog timer.

1

INIT has been triggered by the watchdog timer.

ERST

Meaning

0

No RST has been triggered by the RST pin input.

1

RST has been triggered by the RST pin input.

SRST

Meaning

0

No RST has been triggered by a software reset.