SAM9X25 Atmel Corporation, SAM9X25 Datasheet - Page 271

• Manufacturer Part Number: SAM9X25
• Manufacturer: Atmel Corporation

Specifications of SAM9X25

• Flash (kbytes): 0 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 400 MHz
• Cpu: ARM926
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 105
• Ext Interrupts: 105
• Usb Transceiver: 3
• Usb Speed: Hi-Speed
• Usb Interface: Host, Device
• Spi: 2
• Twi (i2c): 3
• Uart: 7
• Can: 2
• Lin: 4
• Ssc: 1
• Ethernet: 2
• Sd / Emmc: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 12
• Adc Resolution (bits): 10
• Adc Speed (ksps): 440
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: DDR/LPDDR, SDRAM/LPSDR
• 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
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

Figure 24-4. Start Bit Detection
Figure 24-5. Character Reception
24.5.2.3
Figure 24-6. Receiver Ready
24.5.2.4
Figure 24-7. Receiver Overrun
24.5.2.5
11054A–ATARM–27-Jul-11
11054A–ATARM–27-Jul-11
Receiver Ready
Receiver Overrun
Parity Error
Example: 8-bit, parity enabled 1 stop
Sampling
RXRDY
Sampling Clock
RXRDY
OVRE
DRXD
DRXD
DRXD
Baud Rate
DRXD
Clock
S
S
When a complete character is received, it is transferred to the DBGU_RHR and the RXRDY sta-
tus bit in DBGU_SR (Status Register) is set. The bit RXRDY is automatically cleared when the
receive holding register DBGU_RHR is read.
If DBGU_RHR has not been read by the software (or the Peripheral Data Controller or DMA
Controller) since the last transfer, the RXRDY bit is still set and a new character is received, the
OVRE status bit in DBGU_SR is set. OVRE is cleared when the software writes the control reg-
ister DBGU_CR with the bit RSTSTA (Reset Status) at 1.
Each time a character is received, the receiver calculates the parity of the received data bits, in
accordance with the field PAR in DBGU_MR. It then compares the result with the received parity
period
0.5 bit
D0
D0
True Start Detection
D1
D1
period
D2
1 bit
D2
D3
D0
D3
D4
D4
D1
D5
D5
D6
D6
True Start
Detection
D2
D7
D7
P
P
D3
stop
S
S
D4
Read DBGU_RHR
D0
D0
D1
D1
D5
D2
D2
D3
D3
D6
D4
D4
D5
D5
D7
D6
D6
Parity Bit
D7
D7
P
P
stop
Stop Bit
D0
RSTSTA
SAM9X25
SAM9X25
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