Atmel ATmega328 User Manual

46
8271D–AVR–05/11
ATmega48A/PA/88A/PA/168A/PA/328/P
10.11.2 MCUCR – MCU Control Register
• Bit 6 – BODS: BOD Sleep
(1)
The BODS bit must be written to logic one in order to turn off BOD during sleep, see Table 10-1
on page 40. Writing to the BODS bit is controlled by a timed sequence and an enable bit,
BODSE in MCUCR. To disable BOD in relevant sleep modes, both BODS and BODSE must first
be set to one. Then, to set the BODS bit, BODS must be set to one and BODSE must be set to
zero within four clock cycles.
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.
• Bit 5 – BODSE: BOD Sleep Enable
(1)
BODSE enables setting of BODS control bit, as explained in BODS bit description. BOD disable
is controlled by a timed sequence.
Note: 1. BODS and BODSE only available for picoPower devices ATmega48PA/88PA/168PA/328P
10.11.3 PRR – Power Reduction Register
• Bit 7 – PRTWI: Power Reduction TWI
Writing a logic one to this bit shuts down the TWI by stopping the clock to the module. When
waking up the TWI again, the TWI should be re initialized to ensure proper operation.
• Bit 6 – PRTIM2: Power Reduction Timer/Counter2
Writing a logic one to this bit shuts down the Timer/Counter2 module in synchronous mode (AS2
is 0). When the Timer/Counter2 is enabled, operation will continue like before the shutdown.
• Bit 5 – 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 4 – Reserved
This bit is reserved in ATmega48A/PA/88A/PA/168A/PA/328/P 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 7 6 5 4 3 2 1 0
0x35 (0x55) –BODS
(1)
BODSE
(1)
PUD – – IVSEL IVCE MCUCR
Read/Write R R/W R/W R/W R R R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
(0x64) PRTWI PRTIM2 PRTIM0 – PRTIM1 PRSPI PRUSART0 PRADC PRR
Read/Write R/W R/W R/W R R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0

Atmel ATmega328 Specifications

General

Brand	Atmel
Model	ATmega328
Category	Microcontrollers
Language	English