Registers, 1 rsrr: reset cause register, Registers 4.1 rsrr: reset cause register – FUJITSU MB91460 SERIES FR60 User Manual
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Chapter 9 Reset
4.Registers
4. Registers
4.1 RSRR: Reset Cause Register
Stores the cause of the previous reset, and sets the period and activation control for the watchdog timer.
• RSRR: Address 0480h (Access: Byte, Half-word)
Note: See “
Meaning of Bit Attribute Symbols (Page No.10)
” for details of the attributes.
Reading the reset request cause returns the reset cause flags and then clears the flag values to “0”.
If multiple resets occur prior to reading the register, the resulting flag values contain the bitwise OR of the flags
for each reset. That is, more than one flag may be set to “1”.
• 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
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.