ATEVK1104 Atmel, ATEVK1104 Datasheet - Page 395

• Manufacturer Part Number: ATEVK1104
• Description: KIT DEV/EVAL FOR AVR32 AT32UC3A
• Manufacturer: Atmel
• Series: AVR®32r
• Type: MCUr

Specifications of ATEVK1104

• Contents: Evaluation Board, Software and Documentation
• Processor To Be Evaluated: AT32UC3A3
• Data Bus Width: 32 bit
• Interface Type: USB, SPI, USART
• Silicon Manufacturer: Atmel
• Core Architecture: AVR
• Core Sub-architecture: AVR UC3
• Silicon Core Number: AT32UC3A3256
• Silicon Family Name: AVR
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT32UC3A3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

27.6.7.3
Figure 27-29. NWAIT Assertion in Write Access: Ready Mode (EXNW_MODE = 11).
32058J–AVR32–04/11
In te rn a lly s y n c h ro n iz e d
N W A IT s ig n a l
N B S 0 , N B S 1 ,
C L K _ S M C
A 0 , A 1
A [2 5 :2 ]
N W A IT
D [1 5 :0 ]
Ready Mode
N C S
N W E
6
In Ready mode (EXNW_MODE = 11), the SMC behaves differently. Normally, the SMC begins
the access by down counting the setup and pulse counters of the read/write controlling signal. In
the last cycle of the pulse phase, the resynchronized NWAIT signal is examined.
If asserted, the SMC suspends the access as shown in
deassertion, the access is completed: the hold step of the access is performed.
This mode must be selected when the external device uses deassertion of the NWAIT signal to
indicate its ability to complete the read or write operation.
If the NWAIT signal is deasserted before the end of the pulse, or asserted after the end of the
pulse of the controlling read/write signal, it has no impact on the access length as shown in
ure
27-30.
4
5
4
3
3
2
1
2
E X N W _ M O D E = 1 1 (R e a d y m o d e )
W R IT E _ M O D E = 1 (N W E _ c o n tro lle d )
N W E _ P U L S E = 5
N C S _ W R _ P U L S E = 7
W rite c y c le
0
1
F R O Z E N S T A T E
0
1
Figure 27-29
0
1
0
and
AT32UC3A
Figure
27-30. After
Fig-
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