MCU AVR 32K FLASH 32TQFP

ATMEGA328P-AU

Manufacturer Part NumberATMEGA328P-AU
DescriptionMCU AVR 32K FLASH 32TQFP
ManufacturerAtmel
SeriesAVR® ATmega
ATMEGA328P-AU datasheets
 

Specifications of ATMEGA328P-AU

Core ProcessorAVRCore Size8-Bit
Speed20MHzConnectivityI²C, SPI, UART/USART
PeripheralsBrown-out Detect/Reset, POR, PWM, WDTNumber Of I /o23
Program Memory Size32KB (16K x 16)Program Memory TypeFLASH
Eeprom Size1K x 8Ram Size2K x 8
Voltage - Supply (vcc/vdd)1.8 V ~ 5.5 VData ConvertersA/D 8x10b
Oscillator TypeInternalOperating Temperature-40°C ~ 85°C
Package / Case32-TQFP, 32-VQFPProcessor SeriesATMEGA32x
CoreAVR8Data Bus Width8 bit
Data Ram Size2 KBInterface Type2-Wire, SPI, USART
Maximum Clock Frequency20 MHzNumber Of Programmable I/os23
Number Of Timers3Maximum Operating Temperature+ 85 C
Mounting StyleSMD/SMT3rd Party Development ToolsEWAVR, EWAVR-BL
Development Tools By SupplierATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKITMinimum Operating Temperature- 40 C
On-chip Adc10 bit, 8 ChannelCpu FamilyATmega
Device CoreAVRDevice Core Size8b
Frequency (max)20MHzTotal Internal Ram Size2KB
# I/os (max)23Number Of Timers - General Purpose3
Operating Supply Voltage (typ)2.5/3.3/5VOperating Supply Voltage (max)5.5V
Operating Supply Voltage (min)1.8VInstruction Set ArchitectureRISC
Operating Temp Range-40C to 85COperating Temperature ClassificationIndustrial
MountingSurface MountPin Count32
Package TypeTQFPController Family/seriesAVR MEGA
No. Of I/o's23Eeprom Memory Size1KB
Ram Memory Size2KBCpu Speed20MHz
Rohs CompliantYesFor Use WithATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVR
Lead Free Status / RoHS StatusLead free / RoHS CompliantOther namesATMEGA328P-20AU
ATMEGA328P-20AU
Q3790246
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Page 207/566

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ATmega48A/48PA/88A/88PA/168A/168PA/328/328
20.5
Frame Formats
A serial frame for the MSPIM is defined to be one character of 8 data bits. The USART in MSPIM
mode has two valid frame formats:
• 8-bit data with MSB first
• 8-bit data with LSB first
A frame starts with the least or most significant data bit. Then the next data bits, up to a total of
eight, are succeeding, ending with the most or least significant bit accordingly. When a complete
frame is transmitted, a new frame can directly follow it, or the communication line can be set to
an idle (high) state.
The UDORDn bit in UCSRnC sets the frame format used by the USART in MSPIM mode. The
Receiver and Transmitter use the same setting. Note that changing the setting of any of these
bits will corrupt all ongoing communication for both the Receiver and Transmitter.
16-bit data transfer can be achieved by writing two data bytes to UDRn. A UART transmit com-
plete interrupt will then signal that the 16-bit value has been shifted out.
20.5.1
USART MSPIM Initialization
The USART in MSPIM mode has to be initialized before any communication can take place. The
initialization process normally consists of setting the baud rate, setting master mode of operation
(by setting DDR_XCKn to one), setting frame format and enabling the Transmitter and the
Receiver. Only the transmitter can operate independently. For interrupt driven USART opera-
tion, the Global Interrupt Flag should be cleared (and thus interrupts globally disabled) when
doing the initialization.
Note:
Before doing a re-initialization with changed baud rate, data mode, or frame format, be sure that
there is no ongoing transmissions during the period the registers are changed. The TXCn Flag
can be used to check that the Transmitter has completed all transfers, and the RXCn Flag can
be used to check that there are no unread data in the receive buffer. Note that the TXCn Flag
must be cleared before each transmission (before UDRn is written) if it is used for this purpose.
The following simple USART initialization code examples show one assembly and one C func-
tion that are equal in functionality. The examples assume polling (no interrupts enabled). The
8271C–AVR–08/10
To ensure immediate initialization of the XCKn output the baud-rate register (UBRRn) must be
zero at the time the transmitter is enabled. Contrary to the normal mode USART operation the
UBRRn must then be written to the desired value after the transmitter is enabled, but before the
first transmission is started. Setting UBRRn to zero before enabling the transmitter is not neces-
sary if the initialization is done immediately after a reset since UBRRn is reset to zero.
207