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 203/567

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• Bit 5 – UDRIEn: USART Data Register Empty Interrupt Enable n
Writing this bit to one enables interrupt on the UDREn Flag. A Data Register Empty interrupt will
be generated only if the UDRIEn bit is written to one, the Global Interrupt Flag in SREG is written
to one and the UDREn bit in UCSRnA is set.
• Bit 4 – RXENn: Receiver Enable n
Writing this bit to one enables the USART Receiver. The Receiver will override normal port oper-
ation for the RxDn pin when enabled. Disabling the Receiver will flush the receive buffer
invalidating the FEn, DORn, and UPEn Flags.
• Bit 3 – TXENn: Transmitter Enable n
Writing this bit to one enables the USART Transmitter. The Transmitter will override normal port
operation for the TxDn pin when enabled. The disabling of the Transmitter (writing TXENn to
zero) will not become effective until ongoing and pending transmissions are completed, i.e.,
when the Transmit Shift Register and Transmit Buffer Register do not contain data to be trans-
mitted. When disabled, the Transmitter will no longer override the TxDn port.
• Bit 2 – UCSZn2: Character Size n
The UCSZn2 bits combined with the UCSZn1:0 bit in UCSRnC sets the number of data bits
(Character SiZe) in a frame the Receiver and Transmitter use.
• Bit 1 – RXB8n: Receive Data Bit 8 n
RXB8n is the ninth data bit of the received character when operating with serial frames with nine
data bits. Must be read before reading the low bits from UDRn.
• Bit 0 – TXB8n: Transmit Data Bit 8 n
TXB8n is the ninth data bit in the character to be transmitted when operating with serial frames
with nine data bits. Must be written before writing the low bits to UDRn.
20.11.4
UCSRnC – USART Control and Status Register n C
Bit
Read/Write
Initial Value
• Bits 7:6 – UMSELn1:0 USART Mode Select
These bits select the mode of operation of the USARTn as shown in
Table 20-7.
UMSELn1
Note:
8271D–AVR–05/11
ATmega48A/PA/88A/PA/168A/PA/328/P
7
6
5
UMSELn1
UMSELn0
UPMn1
R/W
R/W
R/W
0
0
0
UMSELn Bits Settings
UMSELn0
0
0
0
1
1
0
1
1
1. See
”USART in SPI Mode” on page 206
operation
4
3
2
1
UPMn0
USBSn
UCSZn1
UCSZn0
R/W
R/W
R/W
R/W
0
0
1
1
Table
20-7.
Mode
Asynchronous USART
Synchronous USART
(Reserved)
(1)
Master SPI (MSPIM)
for full description of the Master SPI Mode (MSPIM)
0
UCPOLn
UCSRnC
R/W
0
203