Run Analyzer Starting at Timing Marker

Voters 12

T
H
M
M
D
+ 6 voters
A
?
M
C

Open
Subscribe

Tim

Allow starting a protocol analyzer from a timing marker, like in Logic 1.x (image attached).

Sometimes, the beginning of your data capture may contain junk (for the analyzer) and might cause the analyzer to not decode data properly.

The workaround right now:
Use the Delete Data feature
support.saleae.com/user-guide/using-logic/delete-data

30-01-2021 -

Activity Newest / Oldest

Tim

discuss.saleae.com/t/resynchronising-spi-decoder/2363
"I have an application which is programming a PIC. Normally data is transferred in 4 clock cycle chunks with data locked on falling edge. The SPI protocol decoder works pretty well to see what’s happening.

The catch is that during startup the PIC requires that FIVE clocks be sent before continuing with the normal cycle. This of course throws the SPI protocol decoder into confusion as it thinks that this is four bits of data (all 0) followed by another 0 data bit to start the next 4 bit word.

I’d like to be able to mark a clock rising edge and let the analyser know that it should restart decoding at this point - is that even remotely possible."

Hans

@Saleae:
This functionality is still greatly missed.
Easily analyzing data is to me the basic functionality of a logic analyzer.
(otherwise a scope is a better investment)
The last days I have become annoyed that this functionality still has not been ported to Logic2.
I have another use-case where such a feature is required (deleting data or glitch filter is not a viable work-around).

When working on low level stuff, sometimes, because of limited availability on debug pins, I multiplex both simple pulses and a spi-like output to track states, data, etc.
You can imagine that an spi analyzer will not decode those extra pulses properly.
In Logic1 a simple "restart from timing marker" would be enough to properly decode such a message.

saving a capture, "deleting data", analyzing, restoring the capture, "deleting other data" and analyzing again is not a viable replacement. to inspect 2 messages.

Hans

@Saleae: please put this higher on the requested feature list.
I ran into this missed feature today again.
Sometimes you want to capture a startup or other event where analyzer A is stable (example: external communication)
But analyzer B is only stable after the event (startup of DUT)).

In this usecase deleting data is no option and only specific analyzers need to be restarted.

Tim

discuss.saleae.com/t/spi-decoding-starting-from-a-marker/1674/2
"I cannot find anymore how to decode a spi log (or other protocol) starting from a marker. It was super easy on logic1"
---
"If you are pondering adding a “restart parsing” option a nice feature would be to to tag selected timing markers as restart points or to add restart markers. This would help the case where there are multiple devices on a bus and no available CSs to disambiguate traffic.

A really cool feature would be for Parsing Mode marker info to get passed into HLAs to help manage analysis regions in the data. Just some pipe dreaming going on here, but maybe it influences design decisions?"

Andrés

In the old Logic it was possible to start an analyzer from any arbitrary point.

This is essential for my usage, since I can't usually guarantee the behaviour of all lines except at the time I'm actively using them.

The lack of this feature has unfortunately rendered the SPI and I2C analyzers mostly uesless for me in Logic 2.

Are there any plans to add this feature again?

Tim

Sorry this isn't available in Logic 2 yet. We don't have immediate plans for getting this added, but in the meantime, you can use the "Delete Data" as described here to clean up your capture for the analyzer you are using:
support.saleae.com/user-guide/using-logic/delete-data

Tim

Merged with: Start analyzer from arbitrary location

Tim

(#62565)
"Feature Request - re-run starting at timing marker"

Tim

(#62564)
"Like Logic1.2.29, the data can be parsed from the place after the mark. Solve the problem of some data errors"

Tim

(#62415)
"Not being able to start the SPI decoder at a specific position is a REAL problem in Logic 2. Can you please bring this back?
In my capture, there seems to be no way to delete a portion of the SPI data so that the SPI decoder can work. I know how to make it work, but for that I would need to remove a portion of data IN BETWEEN two markers. That functionality is missing too... I can only delete ALL data before or after a marker..."

Martin

Same problem here. Using Logic2 whilst trying to decode an SPI communication without Enable signal. Porblem is that the logic states of the signals is not correct upon start-up of the device and the logic analyser interprets those as valid, it would be great to have the decoder start after a marker. What I do as a work around is to delete data before the marker but that's not always ideal as I would like to keep that data.

Tim

(#57645)
"Feature Request - In the past it was possible not to start the analyzer from the beginning, but to restart the protocol analysis from a marker.

If there are glitches on the signal, the analyzer no longer works properly because it recognizes the glitches as edges. Then you can restart the analyzer behind the glitch."