Datasheet

33
ATtiny25/45/85 [DATASHEET]
2586Q–AVR–08/2013
chosen if the selcted clock source has a higher frequency than the maximum frequency of the device at the present
operating conditions. The device is shipped with the CKDIV8 Fuse programmed.
Note: The prescaler is disabled in ATtiny15 compatibility mode and neither writing to CLKPR, nor programming the CKDIV8
fuse has any effect on the system clock (which will always be 1.6 MHz).
Table 6-15. Clock Prescaler Select
CLKPS3 CLKPS2 CLKPS1 CLKPS0 Clock Division Factor
0000 1
0001 2
0010 4
0011 8
0100 16
0101 32
0110 64
0111 128
1000 256
1001 Reserved
1010 Reserved
1011 Reserved
1100 Reserved
1101 Reserved
1110 Reserved
1111 Reserved