# Resynchronising SPI decoder

**URL:** <https://discuss.saleae.com/t/resynchronising-spi-decoder/2363>\
**Category:** Support\
**Created:** [August 6, 2023, 11:26am UTC](https://discuss.saleae.com/t/resynchronising-spi-decoder/2363 "2023-08-06T11:26:18Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![david.partridge](https://avatars.discourse-cdn.com/v4/letter/d/5e9695/32.png) [@david.partridge](https://discuss.saleae.com/u/david.partridge)\
**Post date:** [August 6, 2023, 11:26am UTC](https://discuss.saleae.com/t/resynchronising-spi-decoder/2363/1 "2023-08-06T11:26:18Z")

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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.

Thanks  
David

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**Author:** ![timreyes](https://yyz2.discourse-cdn.com/flex030/user_avatar/discuss.saleae.com/timreyes/32/108_2.png) [@timreyes](https://discuss.saleae.com/u/timreyes)\
**Post date:** [August 7, 2023, 11:34pm UTC](https://discuss.saleae.com/t/resynchronising-spi-decoder/2363/2 "2023-08-07T23:34:12Z")

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@david.partridge Unfortunately, starting an analyzer decode process at a specific point in the capture is currently not immediately supported. We’re tracking this feature request below and I’ve added a comment for you to track your need for this. Another user recently reached out to us with their request to implement this feature as well, and I certainly understand your reasoning for needing it.

> **[Run Analyzer Starting at Timing Marker - Logic 2 - Ideas and Feature Requests...](https://ideas.saleae.com/b/feature-requests/run-analyzer-starting-at-timing-marker/)**
>
> 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...

The workaround at the moment is to delete the beginning of the capture, such that the first edge that occurs is where you would like the analyzer to start decoding.

> **[Delete Part of your Capture](https://support.saleae.com/user-guide/using-logic/delete-data)**

We don’t have an estimate as to when we’d be able to work on getting this feature added, but I hope the workaround above can help in the meantime!