Re: [sigrok-devel] UART PD end-of-packet detection by idle timeout

[Kevin G. <ele...@my...>]

On 2022-08-09 05:44, Sergey Spivak wrote:

> I've added the feature of end-of-packet detection by idle timeout to 
> the uart protocol decoder. Here is the pull request:
> 
> https://github.com/sigrokproject/libsigrokdecode/pull/90
> 
> There is feature of combining of the uart data to the packets already. 
> Packet end is determined by amount of data (packet length) or by a 
> delimiter char. But not all uart protocols have constant length of 
> packet or a delimiter char that occurs only at the end of packet. In 
> that cases packets will be splitted at almost random places and 
> therefore it will be difficult to analyze them, especially in realtime 
> using sigrok-cli.
> 
> So I made this little patch that doesn't break any of the existing 
> tests and is limited to adding just this feature to split the uart 
> packets by idle time.
> 
> Does anyone need this feature but me?
> 
> Could someone review the patch and commit it?
> 
> Sincerely yours,
> Sergey Spivak

Hi Sergey,

I haven't looked at your code but I like the idea. In my experience, 
custom uart protocols do sometimes use a quiet gap to frame packets. 
Note the modbus decoder (built on top of the uart decoder) has a gap 
setting for modbus packet framing, but having the option in the uart 
decoder itself is useful IMHO.

I think the best packet framing on uart is achieved with COBS [1] and 
someday I would like to see this decode option in sigrok.

I'm not a sigrok maintainer, just a user. The maintainers are volunteers 
and often have a mountain of PRs to review. Please be patient, it may 
take many months before your PR is attended to.

[1] https://en.wikipedia.org/wiki/Consistent_Overhead_Byte_Stuffing

Regards

Kevin