SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 814

• 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

44.3.6
44.3.6.1
44.3.6.2
44.3.7
44.3.7.1
44.3.7.2
814
AT91SAM9G20
Serial Peripheral Interface (SPI)
Serial Synchronous Controller (SSC)
SPI: Bad Serial Clock Generation on second chip_select when SCBR = 1, CPOL = 1 and NCPHA = 0
SPI: Baudrate set to 1
SSC: Unexpected RK clock cycle when RK outputs a clock during data transfer
SSC: Incorrect first RK clock cycle when RK outputs a clock during data transfer
If the SPI is used in the following configuration:
then an additional pulse will be generated on output PSCK during the second transfer.
Do not use a multiple Chip Select configuration where at least one SCRx register is configured
with SCBR = 1 and the others differ from 1 if CPHA = 0 and CPOL = 1.
If all chip selects are configured with Baudrate = 1, the issue does not appear.
When Baudrate is set to 1 (i.e., when serial clock frequency equals the system clock frequency),
and when the fields BITS (number of bits to be transmitted) equals an ODD value (in this case
9,11,13 or 15), an additional pulse is generated on output SPCK. No error occurs if BITS field
equals 8,10,12,14 or 16 and Baudrate = 1.
None.
When the SSC receiver is used in the following configuration:
then, at the end of the data, the RK pin is set in high impedance which may be interpreted as an
unexpected clock cycle.
Enable the pull-up on RK pin.
When the SSC receiver is used in the following configuration:
then the first clock cycle time generated by the RK pin is equal to MCK/(2 x (DIV +1)) instead of
MCK/(2 x DIV).
• master mode
• CPOL =1 and NCPHA = 0
• multiple chip selects used with one transfer with Baud rate (SCBR) equal to 1 (i.e., when
• transmit with the slowest chip select and then with the fastest one
• the internal clock divider is used (CKS =0 and DIV different from 0),
• RK pin set as output and provides the clock during data transfer (CKO=2)
• data sampled on RK falling edge (CKI =0)
• RX clock is divided clock (CKS = 0 and DIV different from 0)
• RK pin set as output and provides the clock during data transfer (CKO = 2)
• data sampled on RK falling edge (CKI = 0)
serial clock frequency equals the system clock frequency) and the other transfers set with
SCBR not equal to 1
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
6384E–ATARM–05-Feb-10