Datasheet

55
2545T–AVR–05/11
ATmega48/88/168
• Bit 5, 2..0 - WDP3..0: Watchdog timer prescaler 3, 2, 1, and 0
The WDP3..0 bits determine the watchdog timer prescaling when the watchdog timer is running.
The different prescaling values and their corresponding time-out periods are shown in Table 11-
2.
Table 11-2. Watchdog timer prescale select.
WDP3 WDP2 WDP1 WDP0
Number of
WDT oscillator cycles
Typical time-out at
V
CC
= 5.0V
0 0 0 0 2K (2048) cycles 16ms
0 0 0 1 4K (4096) cycles 32ms
0 0 1 0 8K (8192) cycles 64ms
0 0 1 1 16K (16384) cycles 0.125s
0 1 0 0 32K (32768) cycles 0.25s
0 1 0 1 64K (65536) cycles 0.5s
0 1 1 0 128K (131072) cycles 1.0s
0 1 1 1 256K (262144) cycles 2.0s
1 0 0 0 512K (524288) cycles 4.0s
1 0 0 1 1024K (1048576) cycles 8.0s
1010
Reserved
1011
1100
1101
1110
1111