ATmega32C1 Automotive Atmel Corporation, ATmega32C1 Automotive Datasheet - Page 40

• Manufacturer Part Number: ATmega32C1 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega32C1 Automotive

• Flash (kbytes): 32 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 27
• Ext Interrupts: 27
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 1
• Can: 1
• Lin: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 125
• Analog Comparators: 4
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 150
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

6. Power Management and Sleep Modes
6.1
6.1.1
40
Sleep Mode Control Register
Atmel ATmega16/32/64/M1/C1
Sleep Mode Control Register – SMCR
Sleep modes enable the application to shut down unused modules in the MCU, thereby saving
power. The AVR provides various sleep modes allowing the user to tailor the power consump-
tion to the application’s requirements.
To enter any of the five sleep modes, the SE bit in SMCR must be written to logic one and a
SLEEP instruction must be executed. The SM2, SM1, and SM0 bits in the SMCR Register
select which sleep mode (Idle, ADC Noise Reduction, Power-down, Power-save, or Standby)
will be activated by the SLEEP instruction. See
rupt occurs while the MCU is in a sleep mode, the MCU wakes up. The MCU is then halted for
four cycles in addition to the start-up time, executes the interrupt routine, and resumes execu-
tion from the instruction following SLEEP. The contents of the register file and SRAM are
unaltered when the device wakes up from sleep. If a reset occurs during sleep mode, the MCU
wakes up and executes from the Reset Vector.
Figure 5-1 on page 29
and their distribution. The figure is helpful in selecting an appropriate sleep mode.
The Sleep Mode Control Register contains control bits for power management.
• Bits 3..1 – SM2..0: Sleep Mode Select Bits 2, 1, and 0
These bits select between the five available sleep modes as shown in
Table 6-1.
Note:
• Bit 1 – SE: Sleep Enable
The SE bit must be written to logic one to make the MCU enter the sleep mode when the
SLEEP instruction is executed. To avoid the MCU entering the sleep mode unless it is the pro-
grammer’s purpose, it is recommended to write the Sleep Enable (SE) bit to one just before
the execution of the SLEEP instruction and to clear it immediately after waking up.
Bit
Read/Write
Initial Value
SM2
0
0
0
0
1
1
1
1
1. Standby mode is only recommended for use with external crystals or resonators.
Sleep Mode Select
R
7
–
0
SM1
0
0
1
1
0
0
1
1
presents the different clock systems in the ATmega16/32/64/M1/C1,
R
6
–
0
R
5
–
0
SM0
0
1
0
1
0
1
0
1
R
4
–
0
Sleep Mode
Idle
ADC Noise Reduction
Power-down
Reserved
Reserved
Reserved
Standby
Reserved
Table 6-1
SM2
R/W
3
0
(1)
for a summary. If an enabled inter-
SM1
R/W
2
0
SM0
R/W
1
0
Table
6-1.
R/W
SE
0
0
7647G–AVR–09/11
SMCR