SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 478

• Manufacturer Part Number: SAM9G20
• Manufacturer: Atmel Corporation

Specifications of SAM9G20

• Flash (kbytes): 0 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 400 MHz
• Cpu: ARM926
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 96
• Ext Interrupts: 96
• Usb Transceiver: 3
• Usb Speed: Full Speed
• Usb Interface: Host, Device
• Spi: 2
• Twi (i2c): 1
• Uart: 7
• Ssc: 1
• Ethernet: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: Yes
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 95
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 0.9 to 1.1
• Fpu: No
• Mpu / Mmu: No/Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

32.6.3.8
Figure 32-21. Receiver Status
478
Baud Rate
US_RHR
AT91SAM9G20
RXRDY
US_CR
OVRE
Clock
Write
Read
Receiver Operations
RXD
Start
Bit
Figure 32-20. Synchronous Mode Character Reception
When a character reception is completed, it is transferred to the Receive Holding Register
(US_RHR) and the RXRDY bit in the Status Register (US_CSR) rises. If a character is com-
pleted while the RXRDY is set, the OVRE (Overrun Error) bit is set. The last character is
transferred into US_RHR and overwrites the previous one. The OVRE bit is cleared by writing
the Control Register (US_CR) with the RSTSTA (Reset Status) bit at 1.
D0
D1
Example: 8-bit, Parity Enabled 1 Stop
Baud Rate
Sampling
D2
Clock
RXD
D3
D4
D5
Start
D6
D7
Parity
Bit
D0
Stop
Bit
Start
Bit
D1
D0
D1
D2
D2
D3
D3
D4
D4
D5
D6
D5
D7
Parity
Bit
Stop
D6
Bit
RSTSTA = 1
D7
6384E–ATARM–05-Feb-10
Parity Bit
Stop Bit