AT90PWM2B-16SE ATMEL [ATMEL Corporation], AT90PWM2B-16SE Datasheet - Page 49

• Manufacturer Part Number: AT90PWM2B-16SE
• Description: 8-bit Microcontroller with 8K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

9.0.6
9.0.7
4317J–AVR–08/10
Watchdog Reset
MCU Status Register – MCUSR
Figure 9-5.
When the Watchdog times out, it will generate a short reset pulse of one CK cycle duration. On
the falling edge of this pulse, the delay timer starts counting the Time-out period t
page 50
Figure 9-6.
The MCU Status Register provides information on which reset source caused an MCU reset.
• Bit 3 – WDRF: Watchdog Reset Flag
This bit is set if a Watchdog Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 2 – BORF: Brown-out Reset Flag
This bit is set if a Brown-out Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 1 – EXTRF: External Reset Flag
Bit
Read/Write
Initial Value
for details on operation of the Watchdog Timer.
Brown-out Reset During Operation
Watchdog Reset During Operation
CC
INTERNAL
TIME-OUT
R
7
–
0
RESET
RESET
V
CC
R
6
–
0
R
5
–
0
V
CK
BOT-
R
4
–
0
WDRF
R/W
3
AT90PWM2/3/2B/3B
BORF
R/W
2
See Bit Description
V
t
TOUT
BOT+
EXTRF
R/W
1
PORF
R/W
0
TOUT
. Refer to
MCUSR
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