Rainbow Electronics ATmega32L - Manual (Page 25)

25
ATmega32(L)
2503C–AVR–10/02
The CKSEL0 Fuse together with the SUT1..0 fuses select the start-up times as shown in
Table 5.
Notes: 1. These options should only be used when not operating close to the maximum fre-
quency of the device, and only if frequency stability at start-up is not important for the
application. These options are not suitable for crystals.
2. These options are intended for use with ceramic resonators and will ensure fre-
quency stability at start-up. They can also be used with crystals when not operating
close to the maximum frequency of the device, and if frequency stability at start-up is
not important for the application.
Table 5. Start-up Times for the Crystal Oscillator Clock Selection
CKSEL0 SUT1..0
Start-up Time from
Power-down and
Power-save
Additional Delay
from Reset
(V
CC
= 5.0V) Recommended Usage
0 00 258 CK (1) 4.1 ms
Ceramic resonator, fast
rising power
0 01 258 CK (1) 65 ms
Ceramic resonator, slowly
rising power
0 10 1K CK (2) –
Ceramic resonator, BOD
enabled
0 11 1K CK (2) 4.1 ms
Ceramic resonator, fast
rising power
1 00 1K CK (2) 65 ms
Ceramic resonator, slowly
rising power
1 01 16K CK –
Crystal Oscillator, BOD
enabled
1 10 16K CK 4.1 ms
Crystal Oscillator, fast
rising power
1 11 16K CK 65 ms
Crystal Oscillator, slowly
rising power