ARM Cortex-M3 User Manual

Introduction
ARM DDI 0337G Copyright © 2005-2008 ARM Limited. All rights reserved. 1-9
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The ITM provides the following sources of trace information:
• Software trace. Software can write directly to ITM stimulus registers. This causes
packets to be emitted.
• Hardware trace. These packets are generated by the DWT, and emitted by the
ITM.
• Time stamping. Timestamps are emitted relative to packets.
Chapter 11 System Debug describes the ITM.
1.2.7 MPU
You can configure the implementation to include an MPU to provide memory
protection. The MPU checks access permissions and memory attributes. It contains
eight regions, and an optional background region that implements the default memory
map attributes.
Chapter 9 Memory Protection Unit describes the MPU.
1.2.8 ETM
You can configure the system at implementation to include an ETM. This is a low-cost
trace macrocell that supports instruction trace only.
Chapter 14 Embedded Trace Macrocell describes the ETM.
1.2.9 AHB-AP
You can configure the implementation to include an AHB-AP.
AHB-AP on page 11-39 describes the AHB-AP.
1.2.10 AHB Trace Macrocell interface
You can configure the system at implementation to include an AHB Trace Macrocell
(HTM) interface. If you do not enable this option at the time of implementation, the
HTM interface does not function because the required logic is not included.
1.2.11 TPIU
You can configure the system at implementation to include an TPIU. The TPIU acts as
a bridge between the Cortex-M3 trace data from the ITM, an ETM if present, and an
off-chip Trace Port Analyzer.

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