Protocol analyzer and Logic Analyzer simultaneously

[BFisher]

I would really like to run the PA and the LA simultaneously.  Here is an example of why:  Every once in a while sniffing the I2c bus with the PA, I see "Error" and I'd like to look at the LA to see what the signals were actually doing at that point.  I've seen one similar question where Atilla said that it would not be possible to trigger the LA on an error (too bad!) and another where someone else showed how to do the sniffing on either the LA or the PA.  In addition, some of the documentation seems to talk about triggering multiple virtual instruments with the same signal (in this case it would be an I2c start).  But anything I try either gives me an error or else when I start the LA it stops the PA (or vice versa). 

Is anything like this possible?  It seems like a potentially important feature!  Thanks!

[attila]

Hi @BFisher

The Protocol tool uses the Pattern Generator device resource to send, to drive the outputs, and Logic Analyzer device resource for reception, compressed data of significant bits for the respective protocol. These bits are further interpreted in the software.
The errors could be caused by ringing or crosstalk between signals. Try enabling the 'Glitch filter' option, twist each signal wire separately with GND wire.

[BFisher]

I'm a bit unsure what you are saying in the first sentence.  I probably should have said that I am spying in all cases, not driving anything. 

Thanks for the thought about the glitch filter.  I saw elsewhere that the glitch filter depends on having the clock speed set correctly (which was not clear until just now) so that might answer the question about why there is an error.  But I have to say that the ability to have the protocol and LA screens together (not on separate tabs) is a lot less useful if they are not displaying the same signal at the same time.

Thanks! And btw, the protocol analyzer and the protocol-based LA are great and really helpful.

[attila]

Hi @BFisher

Protocol reception and spying use the same device resource as Logic Analyzer, so the two cannot be used at the same time.

[BFisher]

I see.  Too bad, but thanks for the answer.