|
JP1 Remotes
|
View previous topic :: View next topic |
Author |
Message |
Barf Expert
Joined: 24 Oct 2008 Posts: 1415 Location: Munich, Germany |
Posted: Sun Oct 16, 2016 4:51 am Post subject: Samsung36 extra gap |
|
|
Our "official" IRP for the Samsung36 protocol reads
Code: | {38k,500}<1,-1|1,-3>(9,-9,D:8,S:8,1,-9,E:4,F:8,-68u,~F:8,1,-118)+[D:0..255,S:0..255,F:0..255,E:0..15] |
It recently struck me that this description is both implausible and practically awkward for decoding.
The problem is the 68 microseconds gap ("-68u"). It is very implausible that this is a deliberate design from a protocol designer: The bulk of the signal consists of flashes of 500us (micro seconds) duration and gaps of either 500 or 1500us. Then suddenly, a gap of 568 (or 1568) microseconds appears instead of 500 or 1500! It appears very unlikely that this is deliberate. Most receivers (?) would just lump that measurement onto 500 or 1500's.
Also, it makes the recognition of a signal much harder, since the IRP objects are no longer uniquely corresponding to the durations (the last gap of F:8 is being lumped into the -68u).
Comments?
I have not been able to locate a authoritative document describing the protocol. The closest is this one, which does not support the significance of the 68us extra gap.. |
|
Back to top |
|
|
mathdon Expert
Joined: 22 Jul 2008 Posts: 4523 Location: Cambridge, UK |
Posted: Sun Oct 16, 2016 9:13 am Post subject: |
|
|
Barf, I think you may have an out-of-date version of DecodeIR.html. The version in build 14 (the final build) of RMIR v2.03 and in all development versions of RMIR v2.04 has this gap omitted:
Code: | {38k,500}<1,-1|1,-3>(9,-9,D:8,S:8,1,-9,E:4,F:8,~F:8,1,-118)+ |
_________________ Graham |
|
Back to top |
|
|
Barf Expert
Joined: 24 Oct 2008 Posts: 1415 Location: Munich, Germany |
Posted: Sun Oct 16, 2016 10:23 am Post subject: |
|
|
Thanx Graham. I see that the version in SVN is the "sane" version.
The good news is that there is a consensus on the correct version. The bad news is that the "non-sane" version is in official places, like Wiki and the the latest version of DecodeIR. |
|
Back to top |
|
|
mathdon Expert
Joined: 22 Jul 2008 Posts: 4523 Location: Cambridge, UK |
Posted: Sun Oct 16, 2016 11:25 am Post subject: |
|
|
I don't know who deals with the Wiki. DecodeIR is currently maintained by 3FG. _________________ Graham |
|
Back to top |
|
|
mdavej Expert
Joined: 08 Oct 2003 Posts: 4501
|
Posted: Sun Oct 16, 2016 11:36 am Post subject: |
|
|
I just fixed the wiki |
|
Back to top |
|
|
3FG Expert
Joined: 19 May 2009 Posts: 3367
|
Posted: Sun Oct 16, 2016 10:31 pm Post subject: |
|
|
OK, I uploaded the revised DecodeIR.html into the "official" zip file.
However, I think we should be using SourceForge to keep the all of the binaries, docs, and source. When we revised some of the content of DecodeIR.html last January, I checked it in to SF. And the source has been checked in there since Jan 2015. The issue I see with multiple locations is it's easy to get them out of sync. For example, while Dave has fixed the Samsung entry in the Wiki, overall it has obsolete content. |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|