attiny25v ATMEL Corporation, attiny25v Datasheet - Page 28

• Manufacturer Part Number: attiny25v
• Description: Microcontroller With 2/4/8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

28
ATtiny25/45/85
on page
four, providing a 1.6 MHz system clock.
Table 6-6.
Note:
When the calibrated 8 MHz internal oscillator is selected as clock source the start-up times are
determined by the SUT Fuses as shown in
Table 6-7.
Note:
In ATtiny15 Compatibility Mode start-up times are determined by SUT fuses as shown in
6-8
Table 6-8.
Note:
In summary, more information on ATtiny15 Compatibility Mode can be found in sections
(PB5..PB0)” on page
Timer/Counter1 in ATtiny15 Mode” on page
bration Bytes” on page 154
SUT1:0
SUT1:0
10
below..
00
01
11
00
01
10
11
(2)
1. The device is shipped with this option selected.
2. This setting will select ATtiny15 Compatibility Mode, where system clock is divided by four,
1. If the RSTDISBL fuse is programmed, this start-up time will be increased to 14CK + 4 ms to
2. The device is shipped with this option selected.
1. If the RSTDISBL fuse is programmed, this start-up time will be increased to 14CK + 4 ms to
98). Note that in this mode of operation the 6.4 MHz clock signal is always divided by
resulting in a 1.6 MHz clock frequency.
ensure programming mode can be entered.
ensure programming mode can be entered.
CKSEL3:0
Internal Calibrated RC Oscillator Operating Modes
Start-up Times for Internal Calibrated RC Oscillator Clock
Start-up Times for Internal Calibrated RC Oscillator Clock (in ATtiny15 Mode)
0010
0011
from Power-down
from Power-down
(1)
(2)
Start-up Time
Start-up Time
2,
6 CK
6 CK
6 CK
6 CK
6 CK
6 CK
1 CK
“Internal PLL in ATtiny15 Compatibility Mode” on page
and in table
“Clock Prescaler Select” on page
Table 6-7
98,
Additional Delay from
Additional Delay from
Reset (V
Reset (V
“Limitations of debugWIRE” on page
Reserved
14CK + 64 ms
14CK + 64 ms
14CK + 64 ms
14CK + 4 ms
14CK + 4 ms
14CK
14CK
below.
CC
CC
Nominal Frequency
(1)
(1)
= 5.0V)
= 5.0V)
8.0 MHz
6.4 MHz
Recommended Usage
BOD enabled
Fast rising power
Slowly rising power
Recommended Usage
34.
2586K–AVR–01/08
144,
24,
“Port B
“8-bit
Table
“Cali-