AT91SAM7S256C-MU Atmel, AT91SAM7S256C-MU Datasheet - Page 99

• Manufacturer Part Number: AT91SAM7S256C-MU
• Description: IC ARM7 MCU 32BIT 256K 64-QFN
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7S256C-MU

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 55MHz
• Connectivity: I²C, SPI, SSC, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 64K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VQFN Exposed Pad, 64-HVQFN, 64-SQFN, 64-DHVQFN
• Processor Series: AT91
• Core: ARM7TDMI
• Data Bus Width: 32 bit
• Data Ram Size: 64 KB
• Interface Type: SPI, TWI, USART, USB
• Maximum Clock Frequency: 55 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 5
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• For Use With: AT91SAM-ICE - EMULATOR FOR AT91 ARM7/ARM9AT91SAM7S-EK - KIT EVAL FOR ARM AT91SAM7S
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: AT91SAM7S256-MU; AT91SAM7S256-MU

18.3.2.1
18.3.2.2
18.3.3
6175K–ATARM–30-Aug-10
Remap Command
Internal Memory Mapping
Internal Memory Area 0
Within the Internal Memory address space, the Address Decoder of the Memory Controller
decodes eight more address bits to allocate 1-Mbyte address spaces for the embedded
memories.
The allocated memories are accessed all along the 1-Mbyte address space and so are repeated
n times within this address space, n equaling 1M bytes divided by the size of the memory.
When the address of the access is undefined within the internal memory area, the Address
Decoder returns an Abort to the master.
If an access is done in the address area 0x0030 000 to 0x003F FFFF, no abort is generated.
Figure 18-3. Internal Memory Mapping
The first 32 bytes of Internal Memory Area 0 contain the ARM processor exception vectors, in
particular, the Reset Vector at address 0x0.
Before execution of the remap command, the on-chip Flash is mapped into Internal Memory
Area 0, so that the ARM7TDMI reaches an executable instruction contained in Flash. After the
remap command, the internal SRAM at address 0x0020 0000 is mapped into Internal Memory
Area 0. The memory mapped into Internal Memory Area 0 is accessible in both its original loca-
tion and at address 0x0.
After execution, the Remap Command causes the Internal SRAM to be accessed through the
Internal Memory Area 0.
As the ARM vectors (Reset, Abort, Data Abort, Prefetch Abort, Undefined Instruction, Interrupt,
and Fast Interrupt) are mapped from address 0x0 to address 0x20, the Remap Command allows
the user to redefine dynamically these vectors under software control.
The Remap Command is accessible through the Memory Controller User Interface by writing the
MC_RCR (Remap Control Register) RCB field to one.
The Remap Command can be cancelled by writing the MC_RCR RCB field to one, which acts as
a toggling command. This allows easy debug of the user-defined boot sequence by offering a
simple way to put the chip in the same configuration as after a reset.
256M Bytes
0x0000 0000
0x0010 0000
0x0020 0000
0x000F FFFF
0x001F FFFF
0x002F FFFF
0x0FFF FFFF
0x0030 0000
AT91SAM7S Series Preliminary
Internal Memory Area 0
Internal Memory Area 1
Internal Memory Area 2
Undefined Areas
Internal SRAM
Internal Flash
(Abort)
253M bytes
1M Bytes
1M Bytes
1M Bytes
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