ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 75

• Manufacturer Part Number: ATSAM3U-EK
• Description: KIT EVAL FOR AT91SAM3U CORTEX
• Manufacturer: Atmel
• Type: MCUr

Specifications of ATSAM3U-EK

• Contents: Board
• Processor To Be Evaluated: SAM3U
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3 V
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex - M3
• Silicon Core Number: SAM3U4E
• Silicon Family Name: SAM3U
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT91SAM3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6430D–ATARM–25-Mar-11
Table 13-7.
A word access to the SRAM or peripheral bit-band alias regions map to a single bit in the SRAM
or peripheral bit-band region.
The following formula shows how the alias region maps onto the bit-band region:
where:
Figure 13-2
the SRAM bit-band region:
Address
range
0x40000000-
0x400FFFFF
0x42000000-
0x43FFFFFF
• Bit_word_offset is the position of the target bit in the bit-band memory region.
• Bit_word_addr is the address of the word in the alias memory region that maps to the
• Bit_band_base is the starting address of the alias region.
• Byte_offset is the number of the byte in the bit-band region that contains the targeted bit.
• Bit_number is the bit position, 0-7, of the targeted bit.
• The alias word at 0x23FFFFE0 maps to bit[0] of the bit-band byte at 0x200FFFFF: 0x23FFFFE0 =
• The alias word at 0x23FFFFFC maps to bit[7] of the bit-band byte at 0x200FFFFF: 0x23FFFFFC =
• The alias word at 0x22000000 maps to bit[0] of the bit-band byte at 0x20000000: 0x22000000 =
• The alias word at 0x2200001C maps to bit[7] of the bit-band byte at 0x20000000: 0x2200001C =
targeted bit.
0x22000000 + (0xFFFFF*32) + (0*4).
0x22000000 + (0xFFFFF*32) + (7*4).
0x22000000 + (0*32) + (0 *4).
0x22000000+ (0*32) + (7*4).
bit_word_offset = (byte_offset x 32) + (bit_number x 4)
bit_word_addr = bit_band_base + bit_word_offset
shows examples of bit-band mapping between the SRAM bit-band alias region and
Peripheral memory bit-banding regions
Memory
region
Peripheral bit-band
alias
Peripheral bit-band
region
Instruction and data accesses
Direct accesses to this memory range behave as peripheral
memory accesses, but this region is also bit addressable
through bit-band alias.
Data accesses to this region are remapped to bit band
region. A write operation is performed as read-modify-write.
Instruction accesses are not permitted.
SAM3U Series
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