Differences between Live Expressions and SWV

[Mohammad A]

What's the difference between Live Expressions and SWV Data Trace?

Are they both realtime?

Do both of them put a load on MCU processor?

Can I use Live Expressions with MCUs which do not provide SWO pin like CortexM0?

[Markus GIRDLAND · Accepted solution]

Live Expressions does not require any specific peripheral in the MCU which means you can use it with Cortex-M0 while the SWV is required for SWV data trace.

Neither put any real load on the MCU processor.

SWV utilizes timestamps which gives more precise knowledge of when the memory access happened on the target device, live expressions doesn't.

SWV is limited to 4 memory addresses while Live Expression is in theory unlimited while adding many variables will cause slower periodic updates.

The main benefit of Live Expressions is that it's easy to set up and get started and that it works on any Cortex-M.

[Mohammad A]

Thank you. Your answer was perfect.

[Mohammad A]

But one last question, is it safe to use these debug methods in applications where timing is critical?

[Markus GIRDLAND]

It's very precise so it should be. But I don't know the different demands that is required to be certified in different fields such as medical equipment etc.