SAM9G20 Atmel Corporation, SAM9G20 Datasheet - Page 426

• 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

31.7.7
31.7.7.1
31.7.7.2
31.7.8
426
AT91SAM9G20
Using the Peripheral DMA Controller (PDC)
Read-write Flowcharts
Data Transmit with the PDC
Data Receive with the PDC
The use of the PDC significantly reduces the CPU load.
To assure correct implementation, respect the following programming sequences:
The following flowcharts shown in
31-17 on page
read and write operations. A polling or interrupt method can be used to check the status bits.
The interrupt method requires that the interrupt enable register (TWI_IER) be configured first.
1. Initialize the transmit PDC (memory pointers, size, etc.).
2. Configure the master mode (DADR, CKDIV, etc.).
3. Start the transfer by setting the PDC TXTEN bit.
4. Wait for the PDC end TX flag.
5. Disable the PDC by setting the PDC TXDIS bit.
1. Initialize the receive PDC (memory pointers, size - 1, etc.).
2. Configure the master mode (DADR, CKDIV, etc.).
3. Start the transfer by setting the PDC RXTEN bit.
4. Wait for the PDC end RX flag.
5. Disable the PDC by setting the PDC RXDIS bit.
430,
Figure 31-18 on page 431
Figure 31-15 on page
and
Figure 31-19 on page 432
428,
Figure 31-16 on page
6384E–ATARM–05-Feb-10
give examples for
429,
Figure