34
8126F–AVR–05/12
ATtiny13A
• Bits 4:3 – SM[1:0]: Sleep Mode Select Bits 1:0
These bits select between the three available sleep modes as shown in Table 7-2 on page 34.
7.5.3 PRR – Power Reduction Register
The Power Reduction Register provides a method to reduce power consumption by allowing
peripheral clock signals to be disabled.
• Bits 7:2 – Res: Reserved Bits
These bits are reserved and will always read as zero.
• Bit 1 – PRTIM0: Power Reduction Timer/Counter0
Writing a logic one to this bit shuts down the Timer/Counter0 module. When the Timer/Counter0
is enabled, operation will continue like before the shutdown.
• Bit 0 – PRADC: Power Reduction ADC
Writing a logic one to this bit shuts down the ADC. The ADC must be disabled before shut down.
The analog comparator cannot be used when the ADC is shut down.
Table 7-2. Sleep Mode Select
SM1 SM0 Sleep Mode
00Idle
0 1 ADC Noise Reduction
1 0 Power-down
11Reserved
Bit 76543 210
0x25 – – – – – – PRTIM0 PRADC PRR
Read/Write R R R R R R R/W R/W
Initial Value 0 0 0 0 0 0 0 0