ATAVRXPLAIN Atmel, ATAVRXPLAIN Datasheet - Page 6

• Manufacturer Part Number: ATAVRXPLAIN
• Description: KIT EVAL FOR ATXMEGA128A1
• Manufacturer: Atmel
• Series: AVR® XMEGAr
• Type: MCUr

Specifications of ATAVRXPLAIN

• Contents: Board
• Silicon Manufacturer: Atmel
• Core Architecture: AVR
• Silicon Core Number: ATmega128A1
• Silicon Family Name: AVR XMEGA
• Kit Contents: Board
• Rohs Compliant: Yes
• For Use With/related Products: ATXMEGA128A1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2.9 State of Digital I/O Pins
2.10 Virtual Port Registers
2.11 General Purpose I/O Registers
6
AVR1010
It is recommended to use an external 32kHz crystal with X32KLPM enabled. This
gives lower power consumption than the ULP, yet greater accuracy than the internal
RC oscillator. This oscillator may also be used as the system clock source, if such a
low frequency is acceptable.
Table 2-2. Examples of accuracy and current consumption for RTC w/ clock sources.
For Atmel
only the 32kHz crystal oscillator may be used as clock source. In these devices, the
RTC is left running regardless of sleep.
Minimize power consumption by clocking the RTC at 1kHz with an external crystal in
low power mode.
All digital I/O pins are by default floating to avoid hardware conflicts. However, since
the pins have digital input buffers it is important to ensure that the level on an I/O pin
is well-defined to avoid sporadic internal switching and leakage. The leakage caused
by floating I/O is relatively small and is mainly observable in sleep, but can be
minimized by ensuring that the state of the pins is either high or low.
If a pin is connected to an analog source, the digital input buffer on that pin should be
disabled even if it is not configured as an input. This is done by use of the PINnCTRL
registers for the individual ports. Please refer to the device manual for information on
how to do this configuration.
To minimize power consumption, enable pull-up or -down on all unused pins, and
disable the digital input buffer on pins that are connected to analog sources.
To minimize the time spent in ACTIVE mode, virtual port registers can be used. This
allows for single-cycle access with I/O memory specific instructions like IN, OUT and
bit manipulation for the registers DIR, IN, OUT and INTFLAGS for up to four I/O ports.
Use the Virtual Port registers for I/O port access to minimize power consumption.
Another way to minimize the time spent in ACTIVE mode is to use the GPIO registers
for storage of variables. This is also due to the possibility of single-cycle access with
I/O memory specific instructions.
Oscillator
ULP
RC32k
TOSC (32 kHz XTAL)
Notes:
1. At 3V operating voltage.
2. Depends on e.g. quality of crystal.
3. Please refer to the datasheet for exact values and conditions, the values stated
®
AVR
here are meant as guideline only.
®
XMEGA-families with the battery backup module and 32-bit RTC,
2
Accuracy
+/- 30%
+/- 1%
+/- 0,001% (10 ppm)
3
Current consumption
1µA
30µA
0.6µA
8267B-AVR-12/10
1,3