Debugging Tutorial - Part 2: Breakpoints That Don't Stop the Sketch

It is not always intended that breakpoints stop your sketch. You may want your sketch to run uninterrupted, but still want to see where your code passes by. That's when  tracepoints can be used. Tracepoints are like breakpoints, but they do not stop the sketch execution.

How to set tracepoints

The easiest way to create tracepoints instead of breakpoints is to switch to "Debug Trace" mode.

  •  Set the checkmark next to the menu item vMicro > Debug Trace Only
This setting controls all breakpoints, new or existing, and all projects, so this is the best way if you prefer tracepoints generally.

After changing this setting, you must rebuild and upload your sketch again with the blue Stop icon on toolbar toolbar button or vMicro > Build & Upload.

This is how the Output Window looks like if you are working in Debug Trace mode:

Tracepoint Output Window 

From the timestamp at the start of each line, you can see that every loop takes about 10 milliseconds. However, measuring times with tracepoints is not very accurate when it comes to small fractions of time, because the tracepoints themselves need a few milliseconds to send their data to your PC (read more), and there's a built-in limit that makes sure that Visual Micro will not be flooded with messages. You can see that the board sends messages continuously at your board's Receive/Send LEDs flashing.

However, for longer time periods, you can use the tracepoint's timestamp to measure the time spent in an operation.

You can now continue with part 3 of the tutorial:

3.  Text output for breakpoints

 

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