Datasheet

102
XMEGA B [DATASHEET]
8291B–AVR–01/2013
 Bit 6 – USB: USB Module
Setting this bit stops the clock to the USB module. When this bit is cleared, the peripheral should be reinitialized to
ensure proper operation.
 Bit 5 – Reserved
This bit is unused and reserved for future use. For compatibility with future devices, always write this bit to zero when this
register is written.
 Bit 4 – AES: AES Module
Setting this bit stops the clock to the AES module. When this bit is cleared, the peripheral should be reinitialized to
ensure proper operation.
 Bit 3 – Reserved
This bit is unused and reserved for future use. For compatibility with future devices, always write this bit to zero when this
register is written.
 Bit 2 – RTC: Real-Time Counter
Setting this bit stops the clock to the real-time counter. When this bit is cleared, the peripheral should be reinitialized to
ensure proper operation.
 Bit 1 – EVSYS: Event System
Setting this stops the clock to the event system. When this bit is cleared, the module will continue as before it was
stopped.
 Bit 0 – DMA: DMA Controller
Setting this bit stops the clock to the DMA controller. This bit can be set only if the DMA controller is disabled.
8.7.2 PRPA/B – Power Reduction Port A/B register
Note: Disabling of analog modules stops the clock to the analog blocks themselves and not only the interfaces.
 Bit 7:2 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to zero
when this register is written.
 Bit 1 – ADC: Power Reduction ADC
Setting this bit stops the clock to the ADC. The ADC should be disabled before stopped.
 Bit 0 – AC: Power Reduction Analog Comparator
Setting this bit stops the clock to the analog comparator. The AC should be disabled before shutdown.
8.7.3 PRPC/E – Power Reduction Port C/E Register
 Bit 7 – Reserved
This bit is unused and reserved for future use. For compatibility with future devices, always write this bit to zero when this
register is written.
Bit 765432 1 0
+0x01/+0x02
– – – – – – ADC AC
Read/Write RRRRRRR/WR/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
+0x03/+0x04/
+0x05/+0x06
– TWI – USART0 SPI HIRES TC1 TC0
Read/Write R R/W R R/W R/W R/W R/W R/W
Initial Value 0 0000000