Datasheet

34
ATmega8535(L)
2502K–AVR–10/06
asynchronous timer should be considered undefined after wake-up in Power-save mode
if AS2 is 0.
This sleep mode basically halts all clocks except clk
ASY
, allowing operation only of asyn-
chronous modules, including Timer/Counter2 if clocked asynchronously.
Standby Mode When the SM2..0 bits are 110 and an external crystal/resonator clock option is selected,
the SLEEP instruction makes the MCU enter Standby mode. This mode is identical to
Power-down with the exception that the Oscillator is kept running. From Standby mode,
the device wakes up in six clock cycles.
Extended Standby Mode When the SM2..0 bits are 111 and an external crystal/resonator clock option is selected,
the SLEEP instruction makes the MCU enter Extended Standby mode. This mode is
identical to Power-save mode with the exception that the Oscillator is kept running.
From Extended Standby mode, the device wakes up in six clock cycles.
Notes: 1. External Crystal or resonator selected as clock source
2. If AS2 bit in ASSR is set
3. Only INT2 or level interrupt INT1 and INT0
Table 14. Active Clock Domains and Wake-up Sources in the Different Sleep Modes.
Active Clock domains Oscillators Wake up sources
Sleep
Mode
clk
CPU
clk
FLASH
clk
IO
clk
ADC
clk
ASY
Main
Clock
Source
Enabled
Timer
Osc
Enabled
INT2
INT1
INT0
TWI
Address
Match
Timer
2
SPM/
EEPROM
Ready
A
D
C
Other
I/O
Idle X X X X X
(2)
XX X XXX
ADC
Noise
Reduction
XX X X
(2)
X
(3)
XX XX
Power-
down
X
(3)
X
Power-
save
X
(2)
X
(2)
X
(3)
XX
(2)
Standby
(1)
XX
(3)
X
Extended
Standby
(1)
X
(2)
XX
(2)
X
(3)
XX
(2)