AT91SAM9G45-EKES Atmel, AT91SAM9G45-EKES Datasheet - Page 253

• Manufacturer Part Number: AT91SAM9G45-EKES
• Description: KIT EVAL FOR AT91SAM9G45
• Manufacturer: Atmel
• Series: AT91SAM Smart ARMr
• Type: MCUr

Specifications of AT91SAM9G45-EKES

• Contents: Board
• Processor To Be Evaluated: SAM9G45
• Data Bus Width: 32 bit
• Interface Type: I2C, SPI, UART
• Maximum Operating Temperature: + 50 C
• Minimum Operating Temperature: - 10 C
• Operating Supply Voltage: 1.8 V to 3.3 V
• For Use With/related Products: AT91SAM9G45
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: Q4626953

Figure 22-25. Anticipate Precharge/Active Command in Bank 2 during Read Access in Bank 1
6438F–ATARM–21-Jun-10
COMMAND
DQS[1:0]
BA[1:0]
DM1:0]
D[15:0]
A[12:0]
SDClK
NOP
0
3
READ
1
The arbitration type is round-robin arbitration. This algorithm dispatches the requests from differ-
ent masters to the SDRAM device in a round-robin manner. If two or more master requests arise
at the same time, the master with the lowest number is serviced first, then the others are ser-
viced in a round-robin manner. To avoid burst breaking and to provide the maximum throughput
for the SDRAM device, arbitration may only take place during the following cycles:
1. Idle cycles: When no master is connected to the SDRAM device.
2. Single cycles: When a slave is currently doing a single access.
3. End of Burst cycles: When the current cycle is the last cycle of a burst transfer. For
4. Anticipated Access: When an anticipate read access is done while current access is
Anticipate command, Precharge/Active Bank 2
bursts of defined length, predicted end of burst matches the size of the transfer. For
bursts of undefined length, predicted end of burst is generated at the end of each four
beat boundary inside the INCR transfer.
not complete, the arbitration scheme can be changed if the anticipated access is not
the next access serviced by the arbitration scheme.
PRECH
Read access in Bank 1
2
Trp
NOP
Da
Db
ACT
Dc
Dd
READ
1
De
Df
Dg
AT91SAM9G45
Dh
NOP
Di
Dj
Dk
Dl
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