flipperzero-firmware icon indicating copy to clipboard operation
flipperzero-firmware copied to clipboard

Published 20 hours ago • verified publisher icon flipperdevices

Subghz raw sub transmits an unwanted signal at the beginning (OOK 433MHz)

Open coded-with-claws opened this issue 3 years ago • 2 comments

Describe the bug.

Hi!

I'm generating a raw sub file and when I play it with my flipper, it starts with some kind of preamble which I didn't write into the raw sub file:

  • unwanted preamble
    • sends ON for duration ~3000 (selected in blue on the screenshot)
    • sends OFF for ~1000 (just after the selected blue)
  • then applies the content of the raw sub.

I can't see any reason for this behavior, so I'm creating an issue (as I couldn't get info on discord when I asked about that).

Thanks :)

Reproduction

Download the attached .sub.txt file, rename to remove the ".txt" (which was added because of github supported file types). Open it in the Subghz application and hit Send, and capture in urh with a RTL SDR dongle.

pb_rawsub example.sub.txt

Target

No response

Logs

No response

Anything else?

No response

coded-with-claws avatar Oct 24 '22 17:10 coded-with-claws

@Skorpionm do you remember why we start transmission before furi_hal_subghz_start_async_tx is actually started? https://github.com/flipperdevices/flipperzero-firmware/blob/dev/applications/main/subghz/subghz_i.c#L106

skotopes avatar Oct 25 '22 21:10 skotopes

check current dev

Skorpionm avatar Oct 27 '22 06:10 Skorpionm

One more fix and unit tests arrived in latest dev. Please reopen if you still experiencing issue

skotopes avatar Dec 01 '22 17:12 skotopes