ata5773 ATMEL Corporation, ata5773 Datasheet - Page 88

• Manufacturer Part Number: ata5773
• Description: Microcontroller With Uhf Ask/fsk Transmitter
• Manufacturer: ATMEL Corporation

7.5.2
36
ATtiny24/44/84
PRR – Power Reduction Register
both BODS and BODSE must be set to one. Second, within four clock cycles, BODS must be
set to one and BODSE must be set to zero. The BODS bit is active three clock cycles after it is
set. A sleep instruction must be executed while BODS is active in order to turn off the BOD for
the actual sleep mode. The BODS bit is automatically cleared after three clock cycles.
In devices where Sleeping BOD has not been implemented this bit is unused and will always
read zero.
• Bit 5 – 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 programmer’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.
• Bits 4, 3 – SM1..0: Sleep Mode Select Bits 2..0
These bits select between the three available sleep modes as shown in
Table 7-2.
Note:
• Bit 2 – BODSE: BOD Sleep Enable
BOD disable functionality is available in some devices, only. See
The BODSE bit enables setting of BODS control bit, as explained on BODS bit description. BOD
disable is controlled by a timed sequence.
This bit is unused in devices where software BOD disable has not been implemented and will
read as zero in those devices.
The Power Reduction Register provides a method to reduce power consumption by allowing
peripheral clock signals to be disabled.
• Bits 7, 6, 5, 4 - Res: Reserved Bits
These bits are reserved bits in the ATtiny24/44/84 and will always read as zero.
• Bit 3- PRTIM1: Power Reduction Timer/Counter1
Writing a logic one to this bit shuts down the Timer/Counter1 module. When the Timer/Counter1
is enabled, operation will continue like before the shutdown.
Bit
Read/Write
Initial Value
SM1
1. Only recommended with external crystal or resonator selected as clock source
0
0
1
1
Sleep Mode Select
R
7
–
0
SM0
R
6
–
0
0
1
0
1
R
5
–
0
Sleep Mode
Idle
ADC Noise Reduction
Power-down
Standby
R
4
–
0
(1)
PRTIM1
R/W
3
0
PRTIM0
R/W
2
0
“Limitations” on page
PRUSI
R/W
Table 7-2 on page
1
0
PRADC
R/W
0
0
8006G–AVR–01/08
34.
PRR
36.