ATmega165P Atmel Corporation, ATmega165P Datasheet - Page 164

• Manufacturer Part Number: ATmega165P
• Manufacturer: Atmel Corporation

Specifications of ATmega165P

• Flash (kbytes): 16 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 54
• Ext Interrupts: 17
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

18.4.1
8019K–AVR–11/10
Parity Bit Calculation
Figure 18-4. Frame Formats
The frame format used by the USART is set by the UCSZn2:0, UPM1n:0 and USBSn bits in
UCSRnB and UCSRnC. 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.
The USART Character SiZe (UCSZn2:0) bits select the number of data bits in the frame. The
USART Parity mode (UPM1n:0) bits enable and set the type of parity bit. The selection between
one or two stop bits is done by the USART Stop Bit Select (USBSn) bit. The Receiver ignores
the second stop bit. An FEn (Frame Error) will therefore only be detected in the cases where the
first stop bit is zero.
The parity bit is calculated by doing an exclusive-or of all the data bits. If odd parity is used, the
result of the exclusive or is inverted. The relation between the parity bit and data bits is as
follows:
If used, the parity bit is located between the last data bit and first stop bit of a serial frame.
St
(n)
P
Sp
IDLE
P
P
d
even
odd
n
(IDLE)
Start bit, always low.
Data bits (0 to 8)
Parity bit. Can be odd or even.
Stop bit, always high.
No transfers on the communication line (RxD or TxD). An IDLE line must be high.
St
Parity bit using even parity
Parity bit using odd parity
Data bit n of the character
P
0
P
even
odd
1
=
=
2
d
d
n 1
n 1
–
–
3
⊕
⊕
…
…
4
⊕
⊕
FRAME
[5]
d
d
3
3
⊕
⊕
[6]
d
d
2
2
⊕
⊕
[7]
d
d
1
1
[8]
⊕
⊕
d
d
0
0
[P]
⊕
⊕
0
1
Sp1 [Sp2]
ATmega165P
(St/IDLE)
164