AT32UC3L-EK Atmel, AT32UC3L-EK Datasheet - Page 79

• Manufacturer Part Number: AT32UC3L-EK
• Description: KIT EVAL AVR32 UC3 MCU
• Manufacturer: Atmel
• Type: MCUr

Specifications of AT32UC3L-EK

• Contents: *
• Silicon Manufacturer: Atmel
• Core Architecture: AVR
• Core Sub-architecture: UC3L
• Kit Contents: Board
• Features: USB / Battery Powered, Board Controller / Bootloader
• Svhc: No SVHC (15-Dec-2010)
• Rohs Compliant: Yes
• Tool Type: Starter Kit
• Cpu Core: AVR 8
• Data Bus Width: 8 bit
• Processor Series: AT32
• Processor To Be Evaluated: AT32UC3L064
• Interface Type: USB, Capacitive Touch
• For Use With/related Products: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

32099F–11/2010
also the other word in the same 64-bit location is read. The first word is output on the bus, and
the other word is put into an internal buffer. If a read to a sequential address is to be performed
in the next cycle, the buffered word is output on the bus, while the next 64-bit location is read
from the flash memory. Thus, latency in 1 wait state mode is hidden for sequential fetches.
The programmer can select the wait states required by writing to the FWS field in the Flash Con-
trol Register (FCR). It is the responsibility of the programmer to select a number of wait states
compatible with the clock frequency and timing characteristics of the flash memory.
In 0ws mode, no wait states are encountered on any flash read operations. In 1 ws mode, one
stall cycle is encountered on the first access in a single or burst transfer. In 1 ws mode, if the first
access in a burst access is to an address that is not 64-bit aligned, an additional stall cycle is
also encountered when reading the second word in the burst. All subsequent words in the burst
are accessed without any stall cycles.
The Flash Controller provides two sets of buffers that can be enabled in order to speed up
instruction fetching. These buffers can be enabled by writing a one to the FCR.SEQBUF and
FCR.BRBUF bits. The SEQBUF bit enables buffering hardware optimizing sequential instruction
fetches. The BRBUF bit enables buffering hardware optimizing tight inner loops. These buffers
are never used when the flash is in 0 wait state mode. Usually, both these buffers should be
enabled when operating in 1 wait state mode. Some users requiring absolute cycle determinism
may want to keep the buffers disabled.
The Flash Controller address space is displayed in
address pw and the User page is reserved, and reading addresses in this space returns an
undefined result. The User page is permanently mapped to an offset of 0x00800000 from the
start address of the flash memory.
Table 8-1.
Memory type
Main array
User
User Page Addresses
Start address, byte sized
0
0x00800000
Size
pw words = 4pw bytes
64 words = 256 bytes
Figure
AT32UC3L016/32/64
8-1. The memory space between
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