EFM32WG Datasheet, PDF (26/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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6 DBG - Debug Interface
0123 4
ARM Cort e x-M 4
DBG
6.1 Introduction
Debug Data
What?
Quick Facts
The DBG (Debug Interface) is used to
program and debug EFM32WG devices.
Why?
The Debug Interface makes it easy to re-
program and update the system in the field,
and allows debugging with minimal I/O pin
usage.
How?
The Cortex-M4 supports advanced
debugging features. EFM32WG devices
only use two port pins for debugging or
programming. The internal and external state
of the system can be examined with debug
extensions supporting instruction or data
access break- and watch points.
The EFM32WG devices include hardware debug support through a 2-pin serial-wire debug interface
and an Embedded Trace Module (ETM) for data/instruction tracing. In addition, there is also a Serial
Wire Viewer pin which can be used to output profiling information, data trace and software-generated
messages.
6.2 Features
• Flash Patch and Breakpoint (FPB) unit
• Implement breakpoints and code patches
• Data Watch point and Trace (DWT) unit
• Implement watch points, trigger resources and system profiling
• Instrumentation Trace Macrocell (ITM)
• Application-driven trace source that supports printf style debugging
• Embedded Trace Macrocell v3.5 (ETM)
• Real time instruction and data trace information of the processor
6.3 Functional Description
There are three debug pins and four trace pins available on the device. Operation of these pins are
described in the following sections:
6.3.1 Debug Pins
There are three debug pins on the device, which also can be used as GPIO. The three debug pins are:
• Serial Wire Clock input (SWCLK): This pin is enabled after reset and has a built-in pull down.
• Serial Wire Data Input/Output (SWDIO): This pin is enabled after reset and has a built-in pull-up.
• Serial Wire Viewer (SWV): This pin is disabled after reset.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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