ATTINY2313-20PU Atmel, ATTINY2313-20PU Datasheet - Page 123

• Manufacturer Part Number: ATTINY2313-20PU
• Description: IC MCU AVR 2K FLASH 20DIP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY2313-20PU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 18
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-DIP (0.300", 7.62mm)
• Package: 20PDIP
• Device Core: AVR
• Family Name: ATtiny
• Maximum Speed: 20 MHz
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 18
• Interface Type: SPI/USART/USI
• Number Of Timers: 2
• Processor Series: ATTINY2x
• Core: AVR8
• Data Ram Size: 128 B
• Maximum Clock Frequency: 20 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• Cpu Family: ATtiny
• Device Core Size: 8b
• Frequency (max): 20MHz
• Total Internal Ram Size: 128Byte
• # I/os (max): 18
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Through Hole
• Pin Count: 20
• Package Type: PDIP
• For Use With: ATSTK600-DIP40 - STK600 SOCKET/ADAPTER 40-PDIP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Receive Compete Flag
and Interrupt
Receiver Error Flags
2543L–AVR–08/10
Note:
The receive function example reads all the I/O Registers into the Register File before any com-
putation is done. This gives an optimal receive buffer utilization since the buffer location read will
be free to accept new data as early as possible.
The USART Receiver has one flag that indicates the Receiver state.
The Receive Complete (RXC) flag indicates if there are unread data present in the receive buf-
fer. This flag is one when unread data exist in the receive buffer, and zero when the receive
buffer is empty (i.e., does not contain any unread data). If the Receiver is disabled (RXEN = 0),
the receive buffer will be flushed and consequently the RXC bit will become zero.
When the Receive Complete Interrupt Enable (RXCIE) in UCSRB is set, the USART Receive
Complete interrupt will be executed as long as the RXC flag is set (provided that global inter-
rupts are enabled). When interrupt-driven data reception is used, the receive complete routine
must read the received data from UDR in order to clear the RXC flag, otherwise a new interrupt
will occur once the interrupt routine terminates.
The USART Receiver has three error flags: Frame Error (FE), Data OverRun (DOR) and Parity
Error (UPE). All can be accessed by reading UCSRA. Common for the error flags is that they are
located in the receive buffer together with the frame for which they indicate the error status. Due
to the buffering of the error flags, the UCSRA must be read before the receive buffer (UDR),
since reading the UDR I/O location changes the buffer read location. Another equality for the
error flags is that they can not be altered by software doing a write to the flag location. However,
all flags must be set to zero when the UCSRA is written for upward compatibility of future
USART implementations. None of the error flags can generate interrupts.
The Frame Error (FE) flag indicates the state of the first stop bit of the next readable frame
stored in the receive buffer. The FE flag is zero when the stop bit was correctly read (as one),
and the FE flag will be one when the stop bit was incorrect (zero). This flag can be used for
detecting out-of-sync conditions, detecting break conditions and protocol handling. The FE flag
is not affected by the setting of the USBS bit in UCSRC since the Receiver ignores all, except for
the first, stop bits. For compatibility with future devices, always set this bit to zero when writing to
UCSRA.
The Data OverRun (DOR) flag indicates data loss due to a receiver buffer full condition. A Data
OverRun occurs when the receive buffer is full (two characters), it is a new character waiting in
the Receive Shift Register, and a new start bit is detected. If the DOR flag is set there was one
or more serial frame lost between the frame last read from UDR, and the next frame read from
UDR. For compatibility with future devices, always write this bit to zero when writing to UCSRA.
The DOR flag is cleared when the frame received was successfully moved from the Shift Regis-
ter to the receive buffer.
The Parity Error (UPE) Flag indicates that the next frame in the receive buffer had a Parity Error
when received. If Parity Check is not enabled the UPE bit will always be read zero. For compati-
bility with future devices, always set this bit to zero when writing to UCSRA. For more details see
“Parity Bit Calculation” on page 115
1. The example code assumes that the part specific header file is included.
For I/O Registers located in extended I/O map, “IN”, “OUT”, “SBIS”, “SBIC”, “CBI”, and “SBI”
instructions must be replaced with instructions that allow access to extended I/O. Typically
“LDS” and “STS” combined with “SBRS”, “SBRC”, “SBR”, and “CBR”.
and
“Parity Checker” on page
124.
123