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Instruction Trace

The Instruction Trace window applies to non-Cortex-M devices and displays a list of instructions in the order they were executed. Tracing has to be enabled in order to view data in this window.

Instruction Trace button Use the toolbar button or the menu View - Trace - Instruction Trace to open this window.

The picture below is a collage to show various options:

Instruction Trace Window

The column names of have the following meaning:

Instruction Data Description
# A chronological number assigned to each executed instruction.
Type The type of trace listed.
  • ETM - ETM lines contain information captured from the Sync Trace port.
  • ITM - ITM lines contain information captured from the SWO port.
  • O - An Overflow flag indicates that data in the previous trace record was lost because the Cortex-M hardware could not send the requested event information fast enough.
  • D - Delayed Timestamp flag which indicates that the displayed Cycles/Time values are later than the actual event.
  • Note:  The O and D flags may occur on the same line.
Num Number of ETM or ITM Port or Exception Number.
PC The hex address of the executed instruction.
Opcode The assembly language op code in hex.
Instruction The assembly language code line.
Source Code The high-level (C) code source line number and code line with comments.

Double-click a line in this window to switch to the Disassembly window.


  • The look and feel, the filters, and columns of the Instruction Trace window might vary, and depend on the device and the debugger adapter in use.
  • Refer to Trace Data for Cortex-M processor-based devices.
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