SAM9G25 Atmel Corporation, SAM9G25 Datasheet - Page 787

• Manufacturer Part Number: SAM9G25
• Manufacturer: Atmel Corporation

Specifications of SAM9G25

• Flash (kbytes): 0 Kbytes
• Pin Count: 247
• 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
• Lin: 4
• Ssc: 1
• Ethernet: 1
• Sd / Emmc: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: Yes
• 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: DDR2/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

38.10.5.3
Figure 38-27. Master Performs a General Call
38.10.5.4
11032A–ATARM–27-Jul-11
11032A–ATARM–27-Jul-11
GCACC
Clock Synchronization in Read Mode
SVACC
TXD
General Call
Clock Synchronization
S
GENERAL CALL
GENERAL CALL
0000000 + W
The general call is performed in order to change the address of the slave.
If a GENERAL CALL is detected, GACC is set.
After the detection of General Call, it is up to the programmer to decode the commands which
come afterwards.
In case of a WRITE command, the programmer has to decode the programming sequence and
program a new SADR if the programming sequence matches.
Figure 38-27 on page 787
Note:
In both read and write modes, it may happen that TWI_THR/TWI_RHR buffer is not filled /emp-
tied before the emission/reception of a new character. In this case, to avoid sending/receiving
undesired data, a clock stretching mechanism is implemented.
The clock is tied low if the shift register is empty and if a STOP or REPEATED START condition
was not detected. It is tied low until the shift register is loaded.
Figure 38-28 on page 788
This method allows the user to create an own programming sequence by choosing the program-
ming bytes and the number of them. The programming sequence has to be provided to the
master.
WRITE command = 00000100X
A
RESET command = 00000110X
Reset or write DADD
Reset after read
describes the General Call access.
describes the clock synchronization in Read mode.
A
DATA1
Programming sequence
New SADR
A
DATA2
A
New SADR
SAM9G25
SAM9G25
A
P
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