ATmega8535 Atmel Corporation, ATmega8535 Datasheet - Page 33

• Manufacturer Part Number: ATmega8535
• Manufacturer: Atmel Corporation

Specifications of ATmega8535

• Flash (kbytes): 8 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Idle Mode
ADC Noise Reduction
Mode
Power-down Mode
Power-save Mode
2502K–AVR–10/06
When the SM2..0 bits are written to 000, the SLEEP instruction makes the MCU enter
Idle mode, stopping the CPU but allowing SPI, USART, Analog Comparator, ADC, Two-
wire Serial Interface, Timer/Counters, Watchdog, and the interrupt system to continue
operating. This sleep mode basically halts clk
clocks to run.
Idle mode enables the MCU to wake up from external triggered interrupts as well as
internal ones like the Timer Overflow and USART Transmit Complete interrupts. If
wake-up from the Analog Comparator interrupt is not required, the Analog Comparator
can be powered down by setting the ADC bit in the Analog Comparator Control and Sta-
tus register – ACSR. This will reduce power consumption in Idle mode. If the ADC is
enabled, a conversion starts automatically when this mode is entered.
When the SM2..0 bits are written to 001, the SLEEP instruction makes the MCU enter
ADC Noise Reduction mode, stopping the CPU but allowing the ADC, the External Inter-
rupts, the Two-wire Serial Interface address watch, Timer/Counter2 and the Watchdog
to continue operating (if enabled). This sleep mode basically halts clk
FLASH
This improves the noise environment for the ADC, enabling higher resolution measure-
ments. If the ADC is enabled, a conversion starts automatically when this mode is
entered. Apart from the ADC Conversion Complete interrupt, only an External Reset, a
Watchdog Reset, a Brown-out Reset, a Two-wire Serial Interface address match inter-
rupt, a Timer/Counter2 interrupt, an SPM/EEPROM ready interrupt, an external level
interrupt on INT0 or INT1, or an external interrupt on INT2 can wake up the MCU from
ADC Noise Reduction mode.
When the SM2..0 bits are written to 010, the SLEEP instruction makes the MCU enter
Power-down mode. In this mode, the External Oscillator is stopped, while the External
Interrupts, the Two-wire Serial Interface address watch, and the Watchdog continue
operating (if enabled). Only an External Reset, a Watchdog Reset, a Brown-out Reset, a
Two-wire Serial Interface address match interrupt, an external level interrupt on INT0 or
INT1, or an external interrupt on INT2 can wake up the MCU. This sleep mode basically
halts all generated clocks, allowing operation of asynchronous modules only.
Note that if a level triggered interrupt is used for wake-up from Power-down mode, the
changed level must be held for some time to wake up the MCU. Refer to “External Inter-
rupts” on page 68 for details.
When waking up from Power-down mode, there is a delay from the wake-up condition
occurs until the wake-up becomes effective. This allows the clock to restart and become
stable after having been stopped. The wake-up period is defined by the same CKSEL
fuses that define the Reset Time-out period, as described in “Clock Sources” on page
25.
When the SM2..0 bits are written to 011, the SLEEP instruction makes the MCU enter
Power-save mode. This mode is identical to Power-down, with one exception:
If Timer/Counter2 is clocked asynchronously, i.e., the AS2 bit in ASSR is set,
Timer/Counter2 will run during sleep. The device can wake up from either Timer Over-
flow o r Ou tput Comp are event from Tim er/Coun ter2 if the corre sp ond ing
Timer/Counter2 interrupt enable bits are set in TIMSK, and the Global Interrupt Enable
bit in SREG is set.
If the asynchronous timer is NOT clocked asynchronously, Power-down mode is recom-
mended instead of Power-save mode because the contents of the registers in the
, while allowing the other clocks to run.
CPU
and clk
ATmega8535(L)
FLASH
, while allowing the other
I/O
, clk
CPU
, and clk-
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