ATmega168A

Manufacturer Part NumberATmega168A
ManufacturerAtmel Corporation
ATmega168A datasheets
 


Specifications of ATmega168A

Flash (kbytes)16 KbytesPin Count32
Max. Operating Frequency20 MHzCpu8-bit AVR
# Of Touch Channels16Hardware Qtouch AcquisitionNo
Max I/o Pins23Ext Interrupts24
Usb SpeedNoUsb InterfaceNo
Spi2Twi (i2c)1
Uart1Graphic LcdNo
Video DecoderNoCamera InterfaceNo
Adc Channels8Adc Resolution (bits)10
Adc Speed (ksps)15Analog Comparators1
Resistive Touch ScreenNoTemp. SensorYes
Crypto EngineNoSram (kbytes)1
Eeprom (bytes)512Self Program MemoryYES
Dram MemoryNoNand InterfaceNo
PicopowerNoTemp. Range (deg C)-40 to 85
I/o Supply Class1.8 to 5.5Operating Voltage (vcc)1.8 to 5.5
FpuNoMpu / Mmuno / no
Timers3Output Compare Channels6
Input Capture Channels1Pwm Channels6
32khz RtcYesCalibrated Rc OscillatorYes
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Page 78/567

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Note that enabling the alternate function of some of the port pins does not affect the use of the
other pins in the port as general digital I/O.
14.2
Ports as General Digital I/O
The ports are bi-directional I/O ports with optional internal pull-ups.
tional description of one I/O-port pin, here generically called Pxn.
Figure 14-2. General Digital I/O
Note:
14.2.1
Configuring the Pin
Each port pin consists of three register bits: DDxn, PORTxn, and PINxn. As shown in
Description” on page
at the PORTx I/O address, and the PINxn bits at the PINx I/O address.
The DDxn bit in the DDRx Register selects the direction of this pin. If DDxn is written logic one,
Pxn is configured as an output pin. If DDxn is written logic zero, Pxn is configured as an input
pin.
If PORTxn is written logic one when the pin is configured as an input pin, the pull-up resistor is
activated. To switch the pull-up resistor off, PORTxn has to be written logic zero or the pin has to
be configured as an output pin. The port pins are tri-stated when reset condition becomes active,
even if no clocks are running.
8271D–AVR–05/11
ATmega48A/PA/88A/PA/168A/PA/328/P
(1)
Pxn
SLEEP
PUD:
PULLUP DISABLE
SLEEP:
SLEEP CONTROL
clk
:
I/O CLOCK
I/O
1. WRx, WPx, WDx, RRx, RPx, and RDx are common to all pins within the same port. clk
SLEEP, and PUD are common to all ports.
94, the DDxn bits are accessed at the DDRx I/O address, the PORTxn bits
Figure 14-2
shows a func-
PUD
Q
D
DDxn
Q
CLR
WDx
RESET
RDx
1
Q
D
0
PORTxn
Q
CLR
RESET
WPx
WRx
RRx
SYNCHRONIZER
RPx
D
Q
D
Q
PINxn
Q
L
Q
clk
I/O
WDx:
WRITE DDRx
RDx:
READ DDRx
WRx:
WRITE PORTx
RRx:
READ PORTx REGISTER
RPx:
READ PORTx PIN
WPx:
WRITE PINx REGISTER
,
I/O
”Register
78