SAM9XE512 Atmel Corporation, SAM9XE512 Datasheet - Page 133

• Manufacturer Part Number: SAM9XE512
• Manufacturer: Atmel Corporation

Specifications of SAM9XE512

• Flash (kbytes): 512 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 180 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): 2
• Uart: 6
• 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): 312
• 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): 1.65 to 1.95
• Fpu: No
• Mpu / Mmu: No / Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

6.9
ARM DDI 0165B
Busy-waiting and interrupts
ARM processor pipeline
LATECANCEL
Coprocessor pipeline
INSTR[31:0]
CHSD[1:0]
CHSE[1:0]
InMREQ
PASS
CLK
The coprocessor is permitted to stall, or busy-wait, the processor during the execution
of a coprocessor instruction if, for example, it is still busy with an earlier coprocessor
instruction. To do so, the coprocessor associated with the Decode stage instruction
drives WAIT onto CHSD[1:0]. When the instruction concerned enters the Execute
stage of the pipeline the coprocessor can drive WAIT onto CHSE[1:0] for as many
cycles as necessary to keep the instruction in the busy-wait loop.
For interrupt latency reasons, the coprocessor can be interrupted while busy-waiting,
causing the instruction to be abandoned. Abandoning execution is done through PASS.
The coprocessor must monitor the state of PASS during every busy-wait cycle. If it is
HIGH, the instruction must still be executed. If it is LOW, the instruction must be
abandoned. Figure 6-9 shows a busy-waited coprocessor instruction being abandoned
due to an interrupt.
Instr
Copyright © 2000 ARM Limited. All rights reserved.
Execute
Decode
WAIT
Execute
Execute
(WAIT)
(WAIT)
WAIT
Execute
Execute
(WAIT)
(WAIT)
Figure 6-9 ARM9E-S busy waiting and interrupts
WAIT
Execute
Execute
(WAIT)
(WAIT)
Ignored
Interrupted
Execute
Execute
(WAIT)
ARM9E-S Coprocessor Interface
Ignored
Exception
Aban-
doned
Entry
6-17