ARM Cortex-M3 User Manual

Bus Interface
ARM DDI 0337G Copyright © 2005-2008 ARM Limited. All rights reserved. 12-13
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12.10 Bit-band accesses
The System bus interface contains logic that controls bit-band accesses as follows:
• It remaps bit-band alias addresses to the bit-band region.
• For reads, it extracts the requested bit from the read byte, and returns this in the
Least Significant Bit (LSB) of the read data returned to the core.
• For writes, it converts the write to an atomic read-modify-write operation.
For more information about bit-banding, see Bit-banding on page 4-5.
Note
• The Cortex-M3 core does not stall during bit-band operations unless it attempts
to access the System bus while the bit-band operation is being carried out.

ARM Cortex-M3 Specifications

General

Architecture	ARMv7-M
Instruction Set	Thumb-2
Pipeline Stages	3-stage
Interrupts	Nested Vectored Interrupt Controller (NVIC)
Interrupt Controller	Nested Vectored Interrupt Controller (NVIC)
Memory Protection Unit	Optional
Power Consumption	Varies by implementation
Max Clock Speed	Up to 100 MHz
Debugging	JTAG and Serial Wire Debug (SWD)
Operating Voltage	1.8V to 3.6V
Manufacturing Process	Varies by implementation
Core Type	32-bit