AT91SAM9XE512-CU Atmel, AT91SAM9XE512-CU Datasheet - Page 161

• Manufacturer Part Number: AT91SAM9XE512-CU
• Description: MCU ARM9 512K FLASH 217-BGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM9XE512-CU

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 180MHz
• Connectivity: EBI/EMI, Ethernet, I²C, MMC, SPI, SSC, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 96
• Program Memory Size: 512KB (512K x 8)
• Program Memory Type: FLASH
• Ram Size: 56K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 217-LFBGA
• Package: 217LFBGA
• Device Core: ARM926EJ-S
• Family Name: 91S
• Maximum Speed: 180 MHz
• Operating Supply Voltage: 1.8|2.5|3.3 V
• Data Bus Width: 32 Bit
• Number Of Programmable I/os: 96
• Interface Type: EBI/Ethernet/SPI/TWI/USART/USB
• On-chip Adc: 4-chx10-bit
• Number Of Timers: 6
• Processor Series: AT91SAMx
• Core: ARM926EJ-S
• Data Ram Size: 32 KB
• Maximum Clock Frequency: 180 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: JTRACE-ARM-2M, KSK-AT91SAM9XE-PL, MDK-ARM, RL-ARM, ULINK2
• Development Tools By Supplier: AT91SAM-ICE, AT91-ISP, AT91SAM9XE-EK
• Minimum Operating Temperature: - 40 C
• For Use With: AT91SAM9XE-EK - KIT EVAL FOR AT91SAM9XEAT91SAM-ICE - EMULATOR FOR AT91 ARM7/ARM9
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

21.4.1.2
21.4.2
21.4.2.1
21.4.2.2
21.4.2.3
21.4.3
6254C–ATARM–22-Jan-10
Round-Robin Arbitration
Fixed Priority Arbitration
Slot Cycle Limit Arbitration
Round-Robin Arbitration without Default Master
Round-Robin Arbitration with Last Access Master
Round-Robin Arbitration with Fixed Default Master
This selection can be done through the field ULBT of the Master Configuration Registers
(MATRIX_MCFG).
The Bus Matrix contains specific logic to break too long accesses such as very long bursts on a
very slow slave (e.g. an external low speed memory). At the beginning of the burst access, a
counter is loaded with the value previously written in the SLOT_CYCLE field of the related Slave
Configuration Register (MATRIX_SCFG) and decreased at each clock cycle. When the counter
reaches zero, the arbiter has the ability to re-arbitrate at the end of the current byte, half word or
word transfer.
This algorithm allows the Bus Matrix arbiters to dispatch the requests from different masters to
the same slave in a round-robin manner. If two or more master’s requests arise at the same
time, the master with the lowest number is first serviced then the others are serviced in a round-
robin manner.
There are three round-robin algorithms implemented:
This is the main algorithm used by Bus Matrix arbiters. It allows the Bus Matrix to dispatch
requests from different masters to the same slave in a pure round-robin manner. At the end of
the current access, if no other request is pending, the slave is disconnected from all masters.
This configuration incurs one latency cycle for the first access of a burst. Arbitration without
default master can be used for masters that perform significant bursts.
This is a biased round-robin algorithm used by Bus Matrix arbiters. It allows the Bus Matrix to
remove the one latency cycle for the last master that accessed the slave. At the end of the cur-
rent transfer, if no other master request is pending, the slave remains connected to the last
master that performs the access. Other non privileged masters will still get one latency cycle if
they want to access the same slave. This technique can be used for masters that mainly perform
single accesses.
This is another biased round-robin algorithm, it allows the Bus Matrix arbiters to remove the one
latency cycle for the fixed default master per slave. At the end of the current access, the slave
remains connected to its fixed default master. Requests attempted by this fixed default master
do not cause any latency whereas other non privileged masters get one latency cycle. This tech-
nique can be used for masters that mainly perform single accesses.
This algorithm allows the Bus Matrix arbiters to dispatch the requests from different masters to
the same slave by using the fixed priority defined by the user. If two or more master’s requests
are active at the same time, the master with the highest priority number is serviced first. If two or
• Round-Robin arbitration without default master
• Round-Robin arbitration with last access master
• Round-Robin arbitration with fixed default master
AT91SAM9XE128/256/512 Preliminary
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